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M Processor and ® the Intel E7501 Chipset Platform ® ® ® For use with the Intel Pentium M Processor and the Intel ® Pentium M Processor on the 90 nm process with 2-MB L2 cache Design Guide January 2007...
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Intel products are not intended for use in medical, life saving, life sustaining, critical control or safety systems, or in nuclear facility applications. Intel may make changes to specifications and product descriptions at any time, without notice.
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August 2004 Added support for Intel Pentium M Low Voltage 738 Processor. ® ® Added support for the Intel Pentium M Processor on the 90 nm process with 2-MB L2 cache June 2004 Updated recommendation for TEST[1] pin. Changes to the command clock and chip select routing in the Memory July 2003 Interface Guidelines chapter.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Contents Design Guide...
® Intel E7501 Chipset-based systems. Recommendations are subject to change. Board designers may use the associated Intel schematics as a reference. While the schematics cover ® ® a specific design implementation, the core schematics remain the same for most Intel Pentium ®...
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M Processor on the 90 nm Process with 2-MB L2 Cache http://developer.intel.com/design/mobile/ Datasheet datashts/302189.htm ® ® Intel Pentium M Processor on the 90 nm Process with 2-MB L2 Cache http://developer.intel.com/design/mobile/ Specification Update specupdt/302209.htm Note: Contact your Intel Field Representative for additional reference documentation. Design Guide...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Introduction Terminology This section defines terminology used throughout the design guide. Table 2. Conventions and Terminology (Sheet 1 of 4) Terminology Description Aggressor A network that transmits a coupled signal to another network.
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® ® ® Pentium M processor The Intel Pentium M Processor or the Intel Pentium M Processor on the 90 nm process with 2-MB L2 Cache. Both processors share a common design guide. Pin/Ball The contact point of a component package to the traces on a substrate, such as the motherboard.
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E7501 Memory Controller Hub contains an integrated processor and DRAM interface. ® Intel ICH3-S A component of the Intel E7501 chipset, the Intel 82801CA I/O Controller Hub 3-S contains the primary PCI interface, LPC interface, USB, ATA-100, and other legacy functions.
A component of the Intel E7501 chipset, the Intel 82870P2 PCI / PCI-X 64-bit Hub 2 Bus Controller. Hub Interface (HI) Intel high speed proprietary hub interconnect, known as the Hub Interface (HI), ® ® that interfaces the Intel E7501 chipset to the Intel ICH3-S and Intel P64H2.
SpeedStep Technology. Unlike previous implementations of Intel SpeedStep technology, this technology enables the processor to switch between multiple frequency and voltage points instead of two. This will enable superior performance with optimal power savings. Switching between states is software controlled unlike previous implementations where the GHI# pin is used to toggle between two states.
— The processor waits for a fixed time period. If the die temperature is down to acceptable levels, an up transition to the previous frequency/voltage point occurs. — An interrupt is generated for the up and down Intel Thermal Monitor transitions enabling better system level thermal management.
The chipset components communicate through Hub Interfaces (HIs). The MCH provides four Hub Interface connections: one HI1.5 for the ICH3-S and three HI2.0s for high-speed I/O using Intel P64H2 components. The Hub Interfaces are point-to-point and therefore only support two components (the MCH plus one I/O device).
1.3.3.2 I/O Controller Hub 3 (Intel 82801CA ICH3-S) Features ® The I/O Controller Hub 3 (ICH3-S) provides the legacy I/O subsystem for Intel E7501 Chipset- based platforms. Additionally, it integrates many advanced I/O functions. The ICH3-S includes the following features: •...
Hub Interface A Hub Interface B, C, D 1066 PCI-X 1066 1.3.5 System Configurations ® Figure 1 illustrates an example Intel E7501 Chipset-based system configuration for server or ® ® embedded platforms using the Intel Pentium M Processor. Design Guide...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Introduction ® ® ® Figure 1. Intel Pentium M Processor and Intel E7501Chipset-Based System Configuration Example Processor System Memory DDR-200 DDR-200 16-bit PCI / PCI-X HI 2.0 Intel®...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Component Quadrant Layout Component Quadrant Layout The following figures show only general quadrant information, not exact component pin count. Designers should use only the exact pin assignment to conduct routing analyses. Reference the following documents for exact pin assignment information.
Table 4 when designing their boards. Intel realizes numerous ways exist to achieve these targeted impedance tolerances; contact your board vendor for these specifics. Intel encourages platform designers to perform comprehensive simulation analysis to ensure all timing specifications are met. This is particularly important when a design deviates from the design guidelines provided.
• Discrete 0603, 0805 back side. Processor Thermal Solution Placement and Recommended Keep-Outs ® For thermal solution mechanical keep-outs in embedded form factors please refer to the Intel ® Pentium M Processor for Embedded Applications Thermal Design Guide. Design Guide...
Platform Clock Routing Guidelines Platform Clock ® To minimize jitter, improve routing, and reduce cost, Intel E7501 chipset-based systems should use a single chip clock solution, the CK408 or CK408B. The difference between the CK408 and the CK408B is the CK408B provides one additional 100 MHz differential outputs pair. The clock chip provides three (CK408) or four (CK408B) 100 MHz differential output pairs for the processor and MCH, including the ITP connector, and six 66 MHz speed clocks that drive all I/O buses.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Clock Routing Guidelines Table 6. Platform System Clock Reference (Sheet 2 of 2) Clock Group CK-408 Pin Component Component Pin Name 32-bit PCI Connector PCI Video Down...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Clock Routing Guidelines HOST_CLK Clock Group The clock synthesizer provides four sets of 100 MHz differential clock outputs. For this platform three sets of 100 MHz differential clock outputs are used. The 100 MHz differential clocks are driven to the Processor, the MCH, and the processor’s debug port as shown in...
Processor shortest(L1/L1’) = MCH longest(L1/L1’) ± 10 mils. ® ® Additionally, the routing of each half of the host clock pair for the Intel Pentium M processor and MCH should be trace length matched within ± 10 mils of its complement’s routing (i.e., the following relationships should be adhered to): Processor (L1 + L2 + L4) = Processor (L1’...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Clock Routing Guidelines 4.2.3 CK408 vs. CK408B Requirement The CK408 and CK408B are pin compatible. The only difference between the two chips is the CK408B replaces two signals on the CK408 with a fourth HOST_CLK pair. The fourth HOST_CLK pair is connected to the debug port also known as the In Target Probe (ITP).
CLK66 Clock Group In the CLK66 clock group, the driver is the clock synthesizer 66 MHz clock output buffer, and the ® receiver is the 66 MHz clock input buffer at the MCH, Intel ICH3-S, and Intel P64H2. Figure 12.
Each connector is equivalent to 0.60 inch of trace. Adding a single connector on the Intel P64H2 trace would reduce the motherboard trace length by the card length as shown in the following equation and Figure "Z"...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Clock Routing Guidelines Figure 14. Example of Adding a Single Connector NOTES: 1. All lengths must be matched within 100-mils of target length. 2. 66 MHz clock lines routed with 25-mils isolation from any other signal.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Clock Routing Guidelines CLK33_ICH3-S Clock Group For the CLK33_ICH3-S clock group, the driver is the clock synthesizer PCIF 33 MHz clock output buffer, and the receiver is the PCICLK 33 MHz clock input buffer at the ICH3-S. Care must be taken to length match this 33 MHz clock with the ICH3-S 66 MHz clock.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Clock Routing Guidelines CLK14 Clock Group The driver in the CLK14 clock group is the clock synthesizer 14.318 MHz clock output buffer (pin REF0), and the receiver is the 14.318 MHz clock input buffer at the ICH3-S, SIO and LPC.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Clock Routing Guidelines USBCLK Clock Group For the USBCLK clock group, the driver is the clock synthesizer USB clock output buffer (pin USB-48 MHz), and the receiver is the USB clock input buffer at the ICH3-S (pin CLK48).
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Clock Routing Guidelines Clock Driver Decoupling The decoupling requirements for a CK408 compliant clock synthesizer are as follows: • One, 22 µF polarized (decoupling) capacitor placed close to the VDD generation circuitry.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Clock Routing Guidelines Clock Driver Power Delivery Designers must take special care to provide a quiet VDDA supply to the Ref VDD, VDDA and the 48 MHz VDD. These VDDA signals are especially sensitive to switching noise induced by the other VDDs on the clock chip.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Clock Routing Guidelines Design Guide...
The most accurate way to understand the signal integrity and timing of the Intel Pentium M processor system bus in your platform is by performing a comprehensive simulation analysis.
Use this as a quick reference only. The following sections provide more detailed information for each parameter. Intel strongly recommends simulation of all signals to ensure the design meets setup and hold times.
An edge-to-edge trace spacing (2X) to trace-reference plane separation (X) ratio of 2:1 ensures a low crosstalk coefficient. All of the ® effects of crosstalk are difficult to simulate. The timing and layout guidelines for the Intel ® Pentium M processor have been created with the assumption of a 2:1 trace spacing to trace- reference plane ratio.
ITP700FLEX debug port is implemented, a simple point-to-point ® ® connection between the CPURESET# pin of the MCH and Intel Pentium M processor’s RESET# pin is recommended. On-die termination of the AGTL+ buffers on both the processor and the MCH provide proper signal quality for this connection.
It is OK to split different groups of source synchronous signals between different motherboard layers as long as all the signals that belong to that group are kept on the same layer. Grouping of Intel Pentium M processor system bus source synchronous signals is summarized in and Table 20.
For the recommended stack-up example, Figure Skew minimization requires pad-to-pad trace length matching of the Intel Pentium M processor system bus source synchronous signals that belong to the same group including the strobe signals of that group.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform System Bus Routing Guidelines ® ® Table 19. Intel Pentium M Processor System Bus Source Synchronous Data Signal Routing Guidelines Signal Names Total Trace Length Normal Width and...
Although every attempt should be made to maximize the signal spacing in these areas, it is allowable to have 1:1 trace spacing underneath the MCH and the Intel Pentium M processor package outlines and up to <500 mils outside the outer ball array.
Therefore, it is very important to follow the recommended termination voltage for these signals. ® ® 5.1.7.1.1 Topology 1A: Open Drain (OD) Signals Driven by the Intel Pentium M Processor – IERR# The Topology 1A OD signal IERR# should adhere to the following routing and layout recommendations.
V (1.05 V). It is recommended that the FERR# signal of the Intel Pentium M processor be routed to the FERR# signal of the Intel ICH3-S. THERMTRIP# may be implemented in a number of ways to meet design goals.
Table 25 lists the recommended routing requirements for the PROCHOT# signal of the Intel Pentium M processor. The routing guidelines allows the signal to be routed as either a micro-strip or strip-line using 50 Ω ± 10% characteristic trace impedance.
(1.05 V). Note that the Intel ICH3-S CPUPWRGD signal should be routed point-to-point to the Intel Pentium M processor’s PWRGOOD signal. The routing from the Intel Pentium M processor’s PWRGOOD pin should fork out to both the termination resistor, R and the ICH3-S. Segments L1 and L2 from...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform System Bus Routing Guidelines Series resistor R is a component of the voltage translator logic circuit and serves as a driver isolation resistor. R is shown separated by distance L3 from the first bipolar junction transistor (BJT), Q1, to emphasize the placement of Rs with respect to Q1.
M processor, the COMP[2] and COMP[0] pins must each be pulled-down to ground with 27.4 Ω ± 1% resistors and should be connected to the Intel Pentium M processor with a trace impedance of 27.4 Ω. The resistor must be less than 0.5 inches from the processor pins.
M processor has pins that require termination for proper component operation. 1. For the Intel Pentium M processor, a stuffing option should be provided for the TEST[3:1] pins to allow a 1 kΩ ± 5% pull-down to ground for testing purposes. For proper processor operation with the E7501 chipset, only the TEST[1] pin resistor should be stuffed, while the TEST [3:2] resistors should remain unstuffed.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform System Bus Routing Guidelines ® ® 5.1.10 Intel Pentium M Processor V CCSENSE SSSENSE Design Recommendations ® ® The V and V signals of the Intel Pentium M processor provide isolated, low...
Each DDR interface has six signal types: Command Clocks, Source Clocked Signals, Source ® Synchronous Signals, Chip Selects, Clock Enable, and DC Biasing. Refer to the Intel E7501 Chipset Memory Controller Hub (MCH) Datasheet for details on the signals.
DIMM ordering, SMBus Addressing, Command Clock routing and Chip Select routing documented in Figure 36 Figure 37. This addressing must be maintained to be compliant with the reference BIOS code supplied by Intel. Design Guide...
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DIMMs furthest from the MCH when a combination of single-ranked and double-ranked DIMMs is used (see Figure 38). To determine if a registered DDR DIMM is a single-bank DIMM or a double-bank DIMM, contact your local Intel representative for more information. Design Guide...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines Figure 38. Example of Proper Single and Dual Rank Mixing Figure 39. Example of Incorrect Single and Dual Rank Mixing 6.3.1 Dual Channel Source Synchronous Signal Group Routing The MCH source synchronous signals are divided into groups consisting of data bits (DQ) and check bits (CB).
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines Table 32. DQ/CB to DQS Mapping (Sheet 2 of 2) † Data Group Associated Strobe DQ_x[55:48] DQS6, DQS15 DQ_x[63:56] DQS7, DQS16 CB_x[7:0] DQS8, DQS17 †...
E7501 MCH package trace lengths. 3. Route all data signals and their associated strobes on the same layer from MCH to Rtt. 4. The MCH to DIMM1 trace length is defined as Intel E7501 MCH die pad (PCB trace velocity equivalent, see Section 12.6, “Length...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines 6.3.2 Dual Channel Command Clock Routing Only one differential clock pair is routed to each DIMM connector because the MCH only supports registered DDR DIMMs. All CMDCLK/CMDCLK# termination is on the DIMM modules. Route each clock and its compliment adjacent to each other.
The MCH uses DDRCOMP_x to calibrate the DDR channel buffers. This is periodically done by ® sampling the DDRCOMP pin on the MCH. The Intel E7501 MCH calibrates using a 24.9 Ω ± 1% pull-down to ground. This may be implemented by routing a 15 mils wide trace to a...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines Figure 47. Dual Channel DDRCOMP Resistive Compensation <1" DDRCOMP_x 24.9 Ω ± 1% NOTE: ‘x’ indicates channel A or B. 6.3.6.2.1 DDRCOMP Tuning It may be necessary to tune the DDR memory bus for optimum signal integrity based on your platform characteristics.
The ODTCOMP reduces ringbacks and overshoots, and in some cases may help reduce the need for series termination. The Intel E7501 MCH has four DDRVREFs per channel (eight total). Route DDRVREF and ODTCOMP traces 5 mils wide. The ODTCOMP signal needs a 402 Ω pull-down resistor. (See Figure 50.).
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines 6.3.6.4 Dual Channel DDRCVO The MCH uses a compensation signal to adjust buffer characteristics and output voltage swing over temperature, process, and voltage skew. Calibration is done periodically by sampling the DDRCVO_x pins on the MCH.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines Figure 52. DDR VTerm Plane Two Vias Per 1 Capacitor Ground Fill on to the Internal Ground Top Layer One 0.1 µF Decoupling Plane...
DIMMs should be populated furthest when a combination of single ranked and double ranked DIMMs are used. This recommendation is based on the signal integrity requirements of the DDR interface. Intel recommends checking for correct DIMM placement during BIOS initialization. Additionally, it is strongly recommended that all designs follow the DIMM ordering, SMBus...
To determine if a registered DDR DIMM is a single-bank DIMM or a double-bank DIMM, refer to Distinguishing Between Single-Rank and Double-Rank Registered DDR DIMM Modules Application Note (AP-727) or contact your Intel representative for more information. Figure 57. Example of Proper Single Channel Rank Mixing...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines Figure 58. Example of Incorrect Single Channel Rank Mixing 6.4.1 Unused Channel Termination Channel B is not used in a single channel configuration. Therefore, Channel B’s associated signals...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines 6.4.2 Single Channel Source Synchronous Signal Group Routing The MCH source synchronous signals are divided into groups consisting of data bits (DQ) and check bits (CB). An associated strobe (DQS) exists for each DQ and CB group, as shown in Table 42.
3. Route all data signals and their associated strobes on the same layer from MCH to Rtt. 4. The MCH to DIMM1 trace length is defined as Intel E7501 MCH die pad (PCB trace velocity equivalent, Section 12.6, “Length Tuning”) to DIMM1 pin.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines Figure 59. Single Channel Source Synchronous Topology DIMM Solution DDR VTERM (1.25V) DQ/CB Data Group Channel A Associated DQS Rs to DIMM to DIMM...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines 6.4.3 Single Channel Command Clock Routing Only one differential clock pair is routed to each DIMM connector because the MCH only supports registered DDR DIMMs. All CMDCLK/CMDCLK# termination is on the DIMM modules. Route each clock and its compliment adjacent to each other.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines 6.4.4 Single Channel Source Clocked Signal Group Routing The MCH drives the command clock signals and the source-clocked signals together. That is, the MCH drives the command clock in the center of the valid window, and the source-clocked signals propagate with the command clock signal.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines 6.4.5 Single Channel Chip Select Routing The MCH provides eight chip select signals. Two chip selects must be routed to each DIMM (one for each side).
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines 6.4.6 Single Channel Clock Enable Routing The MCH provides a single clock enable (CKE) signal. This signal is used during initialization to indicate that valid power and clocks are being applied to the DIMMs. Because the CKE signal has higher loading, it requires a lower impedance.
The MCH uses DDRCOMP_A to calibrate the DDR channel buffers. This is periodically done by ® sampling the DDRCOMP pin on the MCH. The Intel E7501 MCH calibrates using a 24.9 Ω ± 1% pull-down to ground. This may be implemented by routing a 15 mils wide trace to a...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines Figure 69. Routing Single Channel DDRVREF and ODTCOMP 402 Ω ± 1% ODTCOMP DDR Vref (1.25V) DDRVREF_A3 DDRVREF_A2 DDRVREF_A1 DDRVREF_A0 6.4.7.4 Single Channel DDRCVO The MCH uses a compensation signal to adjust buffer characteristics and output voltage swing over temperature, process, and voltage skew.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Memory Interface Routing Guidelines Figure 71. DDR VTerm Plane Two Vias Per 1 Capacitor Ground Fill on to the Internal Ground Top Layer One 0.1 µF Decoupling Plane...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Hub Interface Hub Interface Signal Naming Convention Figure 74 has the Hub Interface 2.0 and Hub Interface 1.5 signal naming convention for each component. This figure is intended to give a quick naming cross reference to designers. The specific guidelines and implementation on these signals are given in the following sections.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Hub Interface Hub Interface 2.0 Implementation ® The MCH and Intel P64H2 ballout assignments are optimized to simplify the Hub Interface routing between these devices. To allow for greater flexibility in design, a connector may be placed on the interface to access a Hub Interface 2.0 (HI2.0) agent that resides on an adapter card.
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35 mils of spacing from any adjacent signals to minimize effects that cause signal degradation. To break out of the MCH and Intel P64H2 package, the Hub Interface data signals may be routed 5/5 (1:1). The signals must separate to 5/15 (or strobes to 5/35) within 0.5 inch of the outer ball array.
1. All signal lines with arrows depict the total length of the signal including the mother board trace length, MCH ® package trace length, and Intel P64H2 package trace length. 2. PUSTRBF and PUSTRBS length matching is the same as for PSTRBF and PSTRBS.
The nominal Hub Interface 2.0 reference voltage is 0.350 V ± 5%. Each Hub Interface 2.0 on the ® MCH has a dedicated HIVREF pin to sample this reference voltage. Similarly, the Intel P64H2 has a dedicated reference voltage pin. In addition to the reference voltage, a reference swing...
The nominal Hub ® Interface 2.0 reference swing voltage should be 0.8 V ± 5% for the MCH and Intel P64H2. Each Hub Interface 2.0 on the MCH has a dedicated HISWNG pin to sample this reference swing voltage.
Hub Interface 2.0 Decoupling Guidelines ® To improve I/O power delivery, use two, 0.1 µF capacitors per component (i.e., MCH, Intel P64H2). These capacitors should be placed within 150-mils of each package, adjacent to the rows that contain the Hub Interface. When the layout allows, wide metal fingers running on the VSS side of the board should connect the VCC1_8 / VCC1_2 side of the capacitors to the VCC1_8 / VCC1_2 power pins.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Hub Interface Hub Interface 1.5 Implementation The Hub Interface 1.5 signals HI[7:0] are associated with HI_STBS and HI_STBF. For those familiar with Hub Interface 1.0, HI_STBF and HI_STBS are called HI_STB# and HI_STB, respectively.
® 0.7 V ± 5% for the Intel ICH3-S. This voltage is sampled by the MCH using HISWNG, and is sampled by the Intel ICH3-S using HITERM (see Table 58). Both HISWNG and HITERM may be generated locally with a single voltage divider circuit as shown in Figure Table 58.
® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Hub Interface The values of R1, R2, R3, R4 and R5 must be rated at ± 1% tolerance. The selected resistor values must also ensure that the reference voltage and reference swing voltage tolerance are maintained over the input leakage specification.
82870P2 (Intel P64H2) is a peripheral chip that performs PCI/PCI-X bridging functions ® between the Hub Interface 2.0 and the PCI bus. The Intel P64H2 is an integral part of the Intel E7501 chipset, bridging the MCH and the PCI/PCI-X bus. On the primary bus, the Intel P64H2 uses a 16-bit data bus to interface with the Hub Interface 2.0, and on the secondary bus, it supports...
Table 61 itemizes all timing critical and some of the non-critical signals. All of the topologies in the following sections itemize the lengths for the timing critical signals in configurations which Intel simulated. Table 61. Simulated Timing Critical Signals PxAD[63:0], PxC/BE[7:0]#, PxDEVSEL#, PxFRAME#, PxIRDY#, PxTRDY#, PxSTOP#, PxPERR#, PxSERR#,...
Table 63 documents the lengths for the configurations Intel simulated. These topologies may also be used for Hot-Plug Parallel mode configurations where a Hot-Plug switch is not used. Figure 83.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform ® Intel 82870P2 (Intel P64H2) Figure 85 shows a PCI-X channel with a single connector used for a riser. When a one slot riser is used, the channel may be run up to PCI-X 133 MHz. When a three slot riser is used, the channel may be run up to PCI 66 MHz.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform ® Intel 82870P2 (Intel P64H2) Figure 89. Two Devices Down Card Topology Dev ice P64H2 to Dev ice ® Intel P64H2 Dev ice P64H2 to Dev ice Table 69.
PCI-X Addendum to the PCI Local Bus Specification, Revision 1.0a, allows for other resistor values. See Figure 93 for an example of how to implement the ® coupling resistor. IDSEL mapping per Intel P64H2 pin is arbitrary. However, AD16 is reserved. Figure 93. IDSEL Sample Implementation Circuit ®...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform ® Intel 82870P2 (Intel P64H2) Table 73. SMBus Address Configuration Value PAGNT[5] PAGNT[4] PBGNT[5] PBGNT[4] NOTE: There is no bit 0 because it is the read/write direction indicator.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform ® Intel 82870P2 (Intel P64H2) 8.2.1.1 Hot-Removals 1. User selects a slot holding an enabled add-in card and requests that slot be disabled. a. User interacts with a software user interface to request that slot be disabled.
NOTE: The pin names shown in the Intel P64H2 block are Hot-Plug slot signal names. For single-slot parallel mode, refer to Table 76 for the corresponding Intel P64H2 pin name. For dual-slot parallel mode, refer Table 78 for the corresponding Intel P64H2 pin name. Design Guide...
The recommended method to support hot plug is to route the SCI interrupt output signal on the Intel P64H2 (pin PAIRQ7) to an available GPIO pin on the ICH3. A System Controlled Interrupt (SCI) is a system interrupt used by hardware to notify the operating system of ACPI events. SCI is an active-low, shareable, level-triggered interrupt.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform ® Intel 82870P2 (Intel P64H2) 8.2.5 Hot-Plug Interrupt Routing Requirements The recommended method to support Hot-Plug is to route the SCI interrupt output signal on the ® Intel P64H2 (pin PAIRQ7) to an available GPIO pin on the ICH3.
Table 76) to the Hot-Plug controller do not require ® any debouncing logic in this mode. This logic is contained within the Intel P64H2. The POWERON value for this input is determined by BIOS. However, it is recommended that BIOS define a logic 0 to represent that the slot may be powered on.
Note that the placement of the signals should be such that the value driven by the Intel P64H2 in dual-slot parallel mode is the same value it would have driven when in serial mode. 3. In both parallel modes, the BUSEN# and CLKEN# signals become active low instead of active high as they are during serial mode.
Note that the placement of the signals should be such that the value driven by the Intel P64H2 in dual-slot parallel mode is the same value it would have driven when in serial mode. 3. In both parallel modes, the BUSEN# and CLKEN# signals become active low instead of active high as they are during serial mode.
3.3 V through an 8.2 kΩ ± 5% resistor to keep them from toggling. 8.2.7.10 Reference Schematic for Single-Slot Parallel Mode ® Note that the schematic in Figure 99 is based on definition and simulation of the Intel P64H2. The schematic has not been fully validated. Design Guide...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform ® Intel 82870P2 (Intel P64H2) Figure 99. Reference Schematic for Single-Slot Parallel Mode P xP C L K O [0 ] C L K P xP C L K O [6 ]...
The switch inputs (PAIRQ[15] and PAIRQ[10] in this case—see Table 78) to the Hot-Plug ® controller do not require debouncing logic in this mode. This logic is contained within the Intel P64H2. 8.2.8.3 Comparator Circuit for PCIXCAP1/PCIXCAP2 Pins A comparator circuit is required for properly decoding the PCI/PCI-X capability of the slot. Refer to the PCI Local Bus Specification, Revision 2.2, for this circuit.
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LEDs are in the appropriate state (off), and the Q-switches remain disconnected. Note that the placement of the signals should be such that the value driven by the Intel P64H2 in dual slot parallel mode is the same value it would have driven when in serial mode.
P64H2 is ready for it to become deasserted. Pull the PAGNT4 (BUSENB#) signals to 3.3 V through a 10 kΩ ± 5% resistor. The Intel P64H2 may be able to drive this signal to ground when the signal must be asserted.
8.2.9.5 HPx_SLOT[2:0] The HPx_SLOT[2:0] pins are pull-ups/pull-downs that are used to determine the slot count and ® mode of operation for the Intel P64H2 Hot-Plug controller. These pins should be strapped to the proper slot count value. See Table 8.2.9.6...
8.2.10.1 PCIXCAP Pin Requirements During all modes of the Intel P64H2 Hot-Plug controller operation, the Intel P64H2 PCI/PCI-X interface pin PxPCIXCAP is not used. This pin should be tied to VCC3_3 through an 8.2 kΩ resistor to avoid having this line float.
One possible solution to the issue described in the previous paragraphs is to place a single 5 kΩ ± 5% pull-up on the Intel P64H2 side of the isolation logic and a 5 kΩ ± 5% pull-up on the slot side after the isolation logic, but with its own isolation switch, which uses an inverted version of the bus enable control signal.
Intel P64H2 to drive the M66EN signals to ground. The Intel P64H2 PCI interface PxM66EN signal should be pulled to 3.3 V through a 100kΩ ± 5% resistor. This signal would then be connected to the individual slots through a reverse biased diode (one diode per slot).
ICH3-S) IDE Interface ® This section contains guidelines for connecting and routing the Intel ICH3-S IDE interface. The ICH3-S has two independent IDE channels. This section provides guidelines for IDE connector cabling and motherboard design, including component and resistor placement, and signal termination for both IDE channels.
IDE device. When a 40-conductor cable is detected, the system software must not enable modes faster than Ultra DMA Mode 2 (Ultra ATA/33). Intel recommends that cable detection be performed using a combination Host-Side/Device-Side detection mechanism. 9.1.2.1 Combination Host-Side/Device-Side Cable Detection Host-side detection (described in the ATA/ATAPI-4 Standard, Section 5.2.11) requires the use of...
M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) than 2. When ID Word 93, bit 13 is 1, an 80-conductor cable is present. When this bit is 0, a legacy slave (Device 1) is preventing proper cable detection and BIOS should configure the system as though a 40-conductor cable is present and notify the user of the problem.
Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) SPKR Pin Consideration SPKR is used as both the output signal to the system speaker and as a functional strap. The strap function enables or disables the ‘TCO Timer Reboot function’ based on the state of the SPKR pin on the rising edge of PWROK.
® ® Intel Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) Figure 109. PCI Bus Layout Example ® Intel ICH3-S The ICH3-S contains three UHCI host controllers. Each UHCI controller includes a root hub with two separate USB ports, for a total of six USB ports.
® Intel Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) 9.4.2 USB Routing Parameters Use the following separation guidelines. Recommended trace width and separation is 5-mils trace width with 6-mils spacing (90 Ω...
ASIC (e.g., Intel 82550) to access targets on the SMBus as well as the ICH3-S Slave interface. Additionally, the ICH3-S supports slave functionality, including the host Notify protocol, on the SMLink pins.
Wire OR (optional) Controller Note: Intel does not support external access of the ICH3-S's Integrated LAN controller via the SMLink interface. In addition, Intel does not support access of the ICH3-S's SMBus Slave Interface by the ® ICH3-S's SMBus host controller. Refer to the Intel 82801CA I/O Controller Hub 3 (ICH3-S) Datasheet for full functionality descriptions of the SMLink and SMBus interface.
Intel Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) 9.5.2 Unified VCC_CORE Architecture Designing an SMBus using the ICH3-S is based on the power supply source for the SMBus microcontrollers. For the platform, all devices are powered by VCC3_3; therefore, the preferred design choice is the unified VCC3_3 architecture.
® Intel Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) Added Considerations for Mixed Architecture: • The bus switch must be powered by VCC_SUSPEND. • Devices that are powered by the VCC_SUSPEND well must not drive into other devices that are powered off.
Full-Swing 32.768kHz SUSCLK Output Signal ® For further information on the RTC, consult Intel application note AP-728 Intel ICH Family Real Time Clock (RTC) Accuracy and Considerations Under Test Conditions, available at: http://developer.intel.com/design/chipsets/applnots/292276.htm. This section presents the recommended hookup for the RTC circuit for the ICH3-S.
® Intel Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) 9.6.1 RTC External Circuit The ICH3-S RTC module requires an external oscillating source of 32.768 kHz connected on the RTCX1 and RTCX2 balls.
Intel Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) 9.6.3 External Capacitors To maintain the RTC accuracy, the external capacitor C3 must be 0.047 µF, and capacitor values C1 and C2 should be chosen to provide the manufacturer's specified load capacitance (Cload) for the crystal when combined with the parasitic capacitance of the trace, socket (when used), and package.
M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) Note: The temperature dependency of crystal frequency is a parabolic relationship (ppm / degree squared). The effect of the changing crystal's frequency when operating at 0° C (25° C below room temperature) is the same when operating at 50°...
RTC oscillation. Probing VBIAS requires the same technique as probing the RTCX1 and RTCX2 signals (using ® Op-Amp). See application note AP-728, Intel ICH Family Real Time Clock (RTC) Accuracy and Considerations Under Test Conditions, for further details on measuring techniques.
Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) Internal LAN Layout Guidelines The ICH3-S provides various options for integrated LAN capability. The platform supports several components depending on the target market. The guidelines use the term 82562ET to refer to both ®...
Intel Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) 9.7.1 LCI (LAN Connect Interface) Guidelines This section contains guidelines on how to implement a Platform LAN Connect (PLC) device on a system motherboard using LCI. It should not be treated as a specification, and the system designer must ensure through simulations or other techniques that the system meets the specified timings.
Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) • For high-speed signals, the number of corners and vias should be kept to a minimum. When a 90 degree bend is required, it is recommended to use two 45-degree bends instead. Refer to Figure 120.
® Intel Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) • Physically group together all components associated with one clock trace to reduce trace length and radiation. • Isolate I/O signals from high speed signals to minimize crosstalk, which may increase EMI emission and susceptibility to EMI from other signals.
Intel Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) The following are guidelines that help reduce circuit inductance in both backplanes and motherboards: • Route traces over a continuous plane with no interruptions (don't route over a plane split).
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Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) • Lack of symmetry between the two traces within a differential pair. (For each component and/ or via that one trace encounters, the other trace must encounter the same component or a via at the same distance from the PLC.) Asymmetry may create common-mode noise and distort the...
M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) should be exercised when a capacitor is put in either of these locations. When a capacitor is used, it should almost certainly be less than 22 pF (6 pF to 12 pF values have been used on past designs with reasonably good success).
Platform LAN connect component (82562ET or 82562EM) as possible. This is due to the fact that these resistors are terminating the entire impedance that is seen at the termination source (i.e., Intel 82562ET), including the wire impedance reflected through the transformer. Figure 122 shows the Intel 82562ET/EM termination.
9.7.4.2 Distance from Intel® 82562ET to Magnetics Module (Distance B) Distance B should also be designed to be less than 1 inch between devices. The high-speed nature of the signals propagating through these traces requires that the distance between these components be closely observed.
Intel Pentium M Processor and Intel E7501 Chipset Platform ® I/O Controller Hub 3 (Intel ICH3-S) 9.7.5.1 Termination Plane Capacitance It is recommended that the termination plane capacitance equal a minimum value of 1500 pF. This helps reduce the amount of crosstalk on the differential pairs (TDP/TDN and RDP/RDN) from the unused pairs of the RJ45.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Debug Port and Logic Analyzer Interface Debug Port and Logic Analyzer Interface 10.1 ITP Support 10.1.1 Overview One key tool that is needed to debug BIOS, logic, signal integrity, general software, and general hardware issues involving CPUs, chipsets, SIOs, PCI devices, and other hardware in a platform design is the In Target Probe (ITP).
TDI, TMS and TRST# Routing Requirements Route the TDI signal between the ITP700FLEX connector and the Intel Pentium M processor. A 150 Ω ± 5% pull-up to VCCP (1.05 V) should be placed within ± 300 ps of the processor’s TDI pin.
± 200 ps of the ITP700FLEX connector pin. Route the TDO signal from the Intel Pentium M processor to a 54.9 Ω ± 1% pull-up resistor to VCCP that should be placed close to the ITP700FLEX connector’s TDO pin. Then insert a 22.6 Ω...
L3 + L4 – L5 = L2 (within ± 50 ps) There is no need for pull-up termination on the Intel Pentium M processor side of the RESET# net due to presence of AGTL+ on-die termination on the processor and the Intel E7501 MCH.
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Section 10.2.1, “ITP Signal Routing Guidelines”. 3. All of the needed terminations to ensure proper signal quality are integrated inside the Intel Pentium M processor AGTL+ buffers or inside the ITP700FLEX debug port. No need for any external components for the BPM[5:0]# signals.
CPUs, chipsets, SIOs, PCI devices, and other hardware in platform design is the Intel Pentium M processor system bus logic analyzer probe. This tool is widely used by various validation, test, and debug groups from third party BIOS vendors, OEMs, and other developers).
The LAI is installed between the processor socket and the Intel Pentium M processor. The LAI pins plug into the socket, while the Intel Pentium M processor plugs into a socket on the LAI. Cabling this part of the LAI egresses the system to allow an electrical connection between the Intel Pentium M processor and a logic analyzer.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Debug Port and Logic Analyzer Interface Design Guide...
E7501 chipset-based platform. There are many methods to implement a power delivery system, and this is only one example. A voltage regulator (VR) is used to regulate power to the core and Intel Pentium M processor ® system bus rails of the Intel Pentium M processor and the Intel E7501 chipset PSB.
V_3 is the output rail of the 3.3 volt VR. This is typically used to provide power to the VR Controller and miscellaneous logic and pull-ups. 11.2 Customer Reference Board Power Delivery ® ® ® Figure 127 shows the power delivery architecture for the Intel Pentium M processor and Intel E7501 chipset customer reference board. Design Guide...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Power Delivery Guidelines Figure 127. Power Delivery Example Intel® Voltage Vcc_core IMVP-IV Regulator Processor Vcc_core 0.7 - 1.708 V 32 A 0.7 - 1.708 V (Core) (Core) 32 A 2.5 V...
M processor uses six voltage identification pins, VID[5:0], to support automatic selection of power supply voltages. The VID pins for the Intel Pentium M processor are CMOS outputs driven by the processor VID circuitry. For more details about VR design to support the Intel Pentium M processor power supply requirements .
64 mA. This regulator is required in all designs. 11.2.9 1.8 VSB As stated before, the 1.8 VSB provides power to the resume logic within the Intel ICH3-S. This logic uses about 14 mA. This regulator is required in all designs. 11.2.10...
11.3.2 Voltage Identification for Intel Pentium M Processor There are six voltage identification pins on the Intel Pentium M processor. These signals may be used to support automatic selection of V voltages. They are needed to cleanly support CC_CORE voltage specification variations on current and future processors. VID[5:0] is defined in Table 87 below.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Power Delivery Guidelines Table 87. VID vs. V Voltage CC_CORE CC_CORE CC_CORE 1.708 1.196 1.692 1.180 1.676 1.164 1.660 1.148 1.644 1.132 1.628 1.116 1.612 1.100 1.596 1.084...
CPU-PWRGD implemented by platform control logic. ® Figure 128 depicts a number of signals that may or may not be platform visible or used in an Intel ® ® Pentium M processor/Intel E7501 chipset design. For more details on the relationships and timing requirements between VR_ON, output supply stabilization, and all power good signals.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Power Delivery Guidelines regulator may be programmed through an external resistor network. See Figure 129. VREF is used to set the highest output voltage in conjunction with the selection of R5 and R6 in the resistor network.
® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Power Delivery Guidelines These technology improvements by themselves are not sufficient to effectively remove the heat generated during the high current demand and tighter voltage regulation required by today’s processors.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Power Delivery Guidelines Figure 130. Voltage Regulator Multi-Phase Topology Example Voltage Regulator 11.3.7 Voltage Regulator Design Recommendations When laying out the processor power delivery circuit using a traditional Buck Voltage Regulator on...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Power Delivery Guidelines Figure 132. High Current Path With Top MOSFET Turned ON Voltage Regulator Control Circuitry 11.3.7.2 High Current Paths During Abrupt Load Current Changes During abrupt changes in the load current, the bulk and decoupling capacitors must supply current for the brief period before the regulator circuit may respond.
® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Power Delivery Guidelines Dead Time there is a high current flow through the inductor, processor, ground, and the Schottky diode. The diode and its traces must be laid out in such as to minimize both stray inductance and resistance with short, fat traces or planes.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Power Delivery Guidelines • Bulk capacitors for V need three vias per pad when vias are not shared. Clusters of bulk and bypass capacitors may be clustered along the high current paths between the sense resistor and the processor.
11.3.8 Processor Decoupling Recommendations Intel recommends proper design and layout of the system board bulk and high frequency decoupling capacitor solution to meet the transient tolerance at the processor package balls. To meet the transient response of the processor, it is necessary to properly place bulk and high frequency capacitors close to the processor power and ground pins.
10 x 0.1 µF 0.6 nH / 10 Place next to the Intel Pentium M processor CPU. ® † Place one capacitor close to the Intel Pentium M processor and one capacitor close to the Intel E7501 MCH. 11.3.8.5 GTLREF Layout and Routing Recommendations There is one AGTL+ reference voltage pin on the Intel Pentium M processor, GTLREF, which is used to set the reference voltage level for the AGTL+ signals (GTLREF).
Figure 136 shows the recommended topology for generating GTLREF for the Intel Pentium M processor using a R1 = 1 k ± 1% and R2 = 2 k ± 1% resistive divider. Since the input buffer trip point is set by the 2/3* V on GTLREF and to allow tracking of V voltage fluctuations, no decoupling should be placed on the GTLREF pin.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Power Delivery Guidelines • thirteen 0.1 µF capacitors are recommended (with 900 pH to 1.1 nH inductance) and should be evenly spaced for the System Bus. At least seven of the capacitors must be within 0.5 inch of the outer row of balls to the MCH.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Power Delivery Guidelines 11.4.4 Hub Interface (1.2 V Power Plane) Seven, 0.1 µF capacitors should be used to improve I/O power delivery to the MCH. These capacitors should be placed within 150 mils of the MCH package, adjacent to the rows that contain the Hub Interface.
1.8 V logic is powered up. Some signals that are defined as ‘Input-only’ actually have output buffers that are normally disabled, and the Intel ICH3-S may unexpectedly drive these signals when the 3.3 V supply is active while the 1.8 V supply is not.
Ω ± 1% When analyzing systems that may be ‘marginally compliant’ to the Two Volt Rule, attention must be paid to the behavior of the Intel ICH3-S’s RSMRST# and PWROK signals because they control internal isolation logic between the various power planes: •...
0.7 V higher than V5REF. Also, V5REF must power down after VCC3_3, or before VCC3_3 within 0.7 V. The rule must be followed in order to ensure the safety of the Intel ICH3-S. When the rule is violated, internal diodes may attempt to draw power sufficient to damage the diodes from the VCC3_3 rail.
Intel ICH3-S Decoupling Recommendations The Intel ICH3-S is capable of generating large current swings when switching between logic high and logic low. This condition could cause the component voltage rails to drop below specified limits. To avoid this, ensure that the appropriate amount of bulk capacitance is added in parallel to the voltage input pins.
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ICH3-S, Balls B23 and C23. Requires one 0.1 µF decoupling capacitor. V5REF_SUS is the reference voltage for some 5 V tolerant inputs in the Intel ICH3-S (USB data and over current signals). V5REF_SUS VCCSUS_3.3 must never exceed 0.7 V higher than V5REF_SUS.
1.0 µF 100 µF (near regulator) 2.0 (VCC_1.8) † 0.1 µF 4.7 µF (near Intel P64H2) 3.3 V PCI/PCI-X (VCC_3.3) 1.0 µF 100 µF (near regulator) † In the case of the twenty 0.1 µF decoupling capacitors for the Vcc3.3V plane, it is recommended that at...
P64H2 Power Sequencing Requirement The 1.8 V voltage must be valid before the first CLK66 pulse is driven to the Intel P64H2. This may be ensured by gating the CK408 clocks using a power good signal from the 1.8 V regulator. If the first CLK66 pulse is driven before 1.8 V is valid, the Intel P64H2 PLL may fail to correctly...
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Platform Power Delivery Guidelines Design Guide...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns High-Speed Design Concerns 12.1 Return Path The return path is the route current takes to return to its source. It may take a path through ground planes, power planes, other signals, or integrated circuits.
® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns The inductance of the system due to cables and power planes slows the power supply's ability to respond quickly to a current transient. Decoupling a power plane may be broken into several independent parts.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns 12.3 Serpentine Routing A serpentine net is a transmission line that is routed in such a manner that sections of the net double back and couple to other segments of the same net (see Figure 148).
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns 12.4 EMI Design Considerations As microprocessor amperage and speeds increase, the ability to contain the corresponding electromagnetic radiation becomes more difficult. Frequencies generated by these processors may be in the low gigahertz (GHz) range, which may impact both the system design and the electromagnetic interference (EMI) test methodology.
EMI Design Considerations The following sections describe design techniques that may be applied to minimize EMI emissions. Some techniques have been incorporated into Intel-enabled designs (differential clock drivers, selective clock gating, etc.), and some must be implemented by motherboard designers (trace routing, clocking schemes, etc.).
® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns Differential clocking may also reduce the amount of noise coupled to other traces, which improves signal quality and reduces EMI. I/O signals are particularly important because they often leave the system chassis (serial and parallel ports, keyboards, mouse, etc.), and radiate noise that has been...
12.6 Length Tuning ® ® Note: This section does not apply to the Intel Pentium M processor system bus. High speed source synchronous interfaces have very small setup and hold windows. As a result, the signals as a group are very sensitive to skew. A common way to reduce skew is to tune all of the lengths such that the setup and hold windows have the same positional relationship.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns Figure 154. Signal Length Solution Space with One Strobe minimum maximum Minimum_ Maximum_ signal signal Signal Signal flight time flight time Flight Time Flight Time...
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns Figure 156. Signal Length Solution Space with Maximum Tolerance Strobes Minimum_ Maximum_ Signal Signal Flight Time Flight Time Shorter_Strobe Flight Time Longer_Strobe Flight Time tolerance When the strobes have exactly the same flight time, then the signals have a solution space which is 2*tolerance wide.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns 12.6.2 Flight Time Segment Analysis Length matching often requires package compensation. Every time a signal changes innerconnect or layer, there is an affect on flight time. The most effective way to calculate flight time is to break up each signal into segments of constant flight time, analyze those segments, and then add the segment together.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns 12.6.3 Length Tuning Equation Derivation When routing a motherboard, only one piece of the equation is a variable: PCB trace length . For example, when signals are tuned with respect to the strobe, the final equation used by a motherboard designer is derived as follows.
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Tolerance PCB_velocity ® The MCH package velocities and trace lengths are located in the Intel E7501 Chipset Memory Controller Hub (MCH) Datasheet , “Chipset Interface Trace Length Compensation” Chapter. The datasheet states that the trace delay due to signal velocity is the inverse of velocity. The MCH package trace delay due to signal velocity is 150 ps/in, so the velocity is (150 ps/in) .
Intel commonly provides a length tuning calculator spreadsheet. This calculator uses a “seed value.” This is the PCB length of an arbitrary signal, typically the signal with the shortest PCB length.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns To compensate for package-induced skew, all source synchronous motherboard trace lengths are adjusted by the exact amount of Package Length Compensation (PLC). Equation 4 defines PLC for a particular signal.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns Figure 161. Illustration of PLC Length Matching M CH P rocessor Shortest Signal Longest P ackage Longest P ackage P rocessor to M C H...
Intel E7501 Chipset Memory Controller Hub (MCH) Datasheet. Alternatively ® the processor and MCH package trace lengths may be found in the Intel Pentium M Processor System Bus Length Matching Spreadsheet. Contact your Intel representative for information about the Length Matching Spreadsheet tool.
All the signals within the same group are routed to the same length ± 0.1-mil accuracy. The Intel Pentium M processor package traces are routed as micro-strip lines with a nominal characteristic impedance of 50 Ω ± 10%.
To minimize impedance for ground and power pins, like-signals should be tied together whenever possible. Figure 162 shows the proper method for grouping like-signals for the processor and ® Figure 163 shows the MCH grouping. The same methodology should be applied to the Intel ® P64H2 and Intel ICH3-S. Design Guide...
To minimize impedance for ground and power pins, ensure power and ground fills are placed directly under the BGAs. Figure 164 shows the proper method for fills under the MCH. The ® ® same methodology should be applied to the processor, Intel P64H2 and Intel ICH3-S. Figure 164. MCH Fill 2.5V Fill 1.25V Fill 1.2V Fill...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns 12.9.3 Signal Parallelism To minimize high-speed signal induced noise (cross-talk) limit or do not route signals on adjacent layers parallel to each. Figure 165 shows the proper and improper methods for routing signals on adjacent layers.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns 12.9.4 Via Sharing To minimize impedance, traces should not share vias. Figure 166 shows the improper method of via sharing. Figure 167 shows how to correct via sharing.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns Figure 167. Correct Via Sharing C808 and C726 corrected to have their own vias Design Guide...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns 12.9.5 Necking Down To maintain the current carrying capacity of a thicker power/ground trace do not neck the trace down. When a trace is necked down, the entire trace essentially takes on the current carrying capacity of the narrowest width thus decreasing the current capacity effect of the thicker traces.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns Figure 169. Correct Necking Down Neck down corrected by adding additional trace. Traces are equal in length and width. Design Guide...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns 12.9.6 Signals Crossing Plane Splits Signals that cross an adjacent layers plane boundary is undesirable for two reasons: • The return current that runs in the reference plane wants to share its current with the adjacent layers reference plane it just crossed over.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform High-Speed Design Concerns Design Guide...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematic Checklist Schematic Checklist 13.1 Processor Schematic Checklist Table 95. Processor Schematic Checklist (Sheet 1 of 5) Checklist Items Recommendations Comments ® ® Intel Pentium M Processor System Bus (PSB) Interface Signals...
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Refer to Section 5.1.7.1.4. Connect to the processor and the Intel ICH3-S. Connect to the Intel ICH3-S through a 0 Ω series STPCLK# resistor. Include 200 Ω ± 5% pull-up to VCCP. Connect to an Intel ICH-3 GPIO pin or customer...
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematic Checklist Table 95. Processor Schematic Checklist (Sheet 3 of 5) Checklist Items Recommendations Comments • When ITP700FLEX Is Not Used : • Pull up to VCCP with a 150 Ω resistor when –...
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10 µF ± 10% capacitors. • Place all caps near the Processor. Decouple with twelve 0.1 µF ± 10% capacitors VCCP • The Intel Pentium M processor and two 150 µF ± 10% capacitors contains 25 VCC pins. For testing purposes, pull-down to GND through a 54.9 Ω...
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For testing purposes, pull-down to VSSSENSE No Connect GND through a 54.9 Ω ± 1% resistor. ® Processor Signals Not Supported By the Intel E7501 Chipset • No Connect. • For testing purposes, a stuffing option should DPWR# be provided to pull-up to VCCP through a 1 K Ω...
HIT# HITM# HLOCK# HREQ[4:0]# HTRDY# RS[2:0]# XERR# ® ® Signals Not Supported by the Intel Pentium M Processor AP[1:0] BINIT# through a 1 K Ω ± 5% resistor. DP[3:0]# • Pull-up to V RSP# • See schematics for further details on stuffing HA[35:32]# options.
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Intel P64H2 and (For trace impedance = 50 Ω ± 10%). HIRCOMP_C MCH to adjust the buffer HIRCOMP_D • Tie the Intel P64H2’s RCOMP pin to characteristics to specific 61.9 Ω ± 1%, pull-up to 1.8 V. board characteristics. • Refer to Section 7.2.3.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematic Checklist Table 96. MCH Schematic Checklist (Sheet 3 of 4) Checklist Items Recommendations Comments • This signal is used to calibrate the Host AGTL+ I/O buffer Tie each COMP pin to a 24.9 Ω ±1% pull-down...
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematic Checklist Table 96. MCH Schematic Checklist (Sheet 4 of 4) Checklist Items Recommendations Comments 1.2 V Seven 0.1 µF caps. Refer to Section 11.4.4. (Hub Interface) VCCA1_2 VCCAHI1_2 RLC filters.
Asserted by the Intel ICH3-S when Recommend 300 Ω ± 5% pull-up to CPU_VCC. CPUPWRGD all processor voltage supplies are Connect to the processor and the Intel ICH3-S. stable. FWH Interface Signals No extra pull-ups required. Connect straight to The Intel ICH3-S integrates FWH[3:0]/ LAD[3:0] 24 k Ω...
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• No pull-down resistors required. ICH3-S. • Refer to Section 9.1.3. • These signals have integrated • No extra series termination resistors. series resistors in the Intel PIORDY ICH3-S. SIORDY • 4.7 k Ω ± 5% pull-up to 3.3 V • Refer to Section 9.1.3.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematic Checklist ® Table 97. Intel ICH3-S Schematic Checklist (Sheet 3 of 8) Checklist Items Recommendations Comments • The 10 k Ω resistor to GND prevents GPI from floating when no devices are present on either IDE interface.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematic Checklist ® Table 97. Intel ICH3-S Schematic Checklist (Sheet 4 of 8) Checklist Items Recommendations Comments LAN Interface Signals Connect to LAN_CLK on Platform LAN Connect LAN_CLK Device.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematic Checklist ® Table 97. Intel ICH3-S Schematic Checklist (Sheet 5 of 8) Checklist Items Recommendations Comments • These signals have integrated pull-ups of 24 k Ω .
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VCCSUS1.8 have reached their nominal voltages. • 10 k Ω ± 5% pull-down to ground. Disconnect from the Intel ICH3-S and leave not connected. Use 8.2 k Ω pull-up resistor to SUS_STAT# VCC_3.3 for remaining devices on LPC bus.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematic Checklist ® Table 97. Intel ICH3-S Schematic Checklist (Sheet 7 of 8) Checklist Items Recommendations Comments RTC Signals • For noise immunity on VBIAS signal. VBIAS Use one 0.047 µF capacitor.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematic Checklist ® Table 97. Intel ICH3-S Schematic Checklist (Sheet 8 of 8) Checklist Items Recommendations Comments USB Signals 18.2 Ω ± 1% pull-down to ground. USBRBIAS Integrated 15 k Ω pull-down, USBP[5:0]P No external resistors are required.
• R4 = 261 Ω ± 1%, R5 = 332 Ω ± 1%, HI_VSWING R6 = 750 Ω ± 1%. • Decouple the Intel P64H2 pin with a 0.01 µF. • Decouple the network nodes with a 0.1 µF PCI/PCI-X Bus Interface Signals...
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8.2 k Ω ± 5% pull-up to 3.3 V. APICD[1:0] Hot Plug Interface Enabled PxPCIXCAP These PCI signals are connected ® to separate pins on the Intel P64H2. See Section 8.2.7.3, and 8.2 k Ω ± 5% pulled up to 3.3 V. Section 8.2.8.4...
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematic Checklist ® Table 98. Intel P64H2 Schematic Checklist (Sheet 3 of 5) Checklist Items Recommendations Comments A logic one on this pin indicates to the controller that the PCI slot should be immediately powered off.
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• Decoupling: VCC1.8 Refer to Section 11.6.2. – 2 X 1.0 µF capacitors near the Intel P64H2. – 1 X 100.0 µF capacitors near regulator. Connect to 3.3 V Power Supply. Decoupling: • 20 0.1 µF capacitors near the Intel P64H2.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematic Checklist ® Table 98. Intel P64H2 Schematic Checklist (Sheet 5 of 5) Checklist Items Recommendations Comments 8.2 k Ω ± 5% pull-up to VCC3.3. TEST# 8.2 k Ω ± 5% pull-up to VCC3.3.
See schematic for reference circuit. 10 k Ω ± 5% pull-down to ground. FS[1] SCLK, SDTA Connect to the 3 V SMBus partition. Connect to the Intel ICH3-S using a 33 Ω ± 5% USB_48MHz Refer to Section 4.7. series resistor to ICH3_CLK48.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematic Checklist Table 99. CK408 Schematic Checklist (Sheet 2 of 2) Checklist Items Recommendations Reason/Impact VSS, VSS_48MHz, Terminate to GND. Refer to Section 4.9. VSS_IREF 1 k Ω ± 5% pull-down to ground.
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Layout Checklist Layout Checklist All trace width and spacing recommendations are derived from a target impedance and crosstalk sensitivity. This is based upon the stackup defined in Section 3.1.
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7.5 inches. RESET# RS[2:0]# TRDY# ICH3-S Interface Signals ® • Connect to the processor and the Intel ICH3-S. A20M# • Trace impedance = 50 Ω ± 10%. IGNNE# INIT# • Route traces using 5/10 mils (1:2) spacing.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Layout Checklist Table 100. Processor Layout Checklist (Sheet 3 of 4) Checklist Items Recommendations Comments Processor In Target Probe (ITP) Signals When ITP700FLEX Is Used : Point to point connection to CPU pin.
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Layout Checklist Table 100. Processor Layout Checklist (Sheet 4 of 4) Checklist Items Recommendations Comments Processor Power and GND Signals • To satisfy damping requirements, total series resistance in the filter (from CPU_VCC to the top plate of the capacitor) must be at least 0.35 Ω...
® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Layout Checklist ® 14.3 Intel ICH3-S Layout Checklist ® Table 102. Intel ICH3-S Layout Checklist (Sheet 1 of 4) Checklist Items Recommendations Comments Processor Signals A20M# CPUSLP# FERR# IGNNE# See processor section of this checklist.
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(4.7 µF or greater OK) on each side of the that this is a robust design Intel 82562EM / Intel 82562ET component. recommendation. Place decoupling capacitors (0.1 µF) as close to the Intel 82562EM / Intel 82562ET component as possible. Design Guide...
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Comments Power Decoupling Use one 0.1 µF decoupling capacitor. V_CPU_IO[2:0] Locate within 100 mils of the Intel ICH3-S Used to pull-up all processor I/F signals. processor interface balls. Requires six 0.1 µF decoupling capacitors. Distribute around the Intel ICH3-S package...
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(such as USBP2P and USBP2N) should be no greater than 150 mils. • No termination resistors needed for USB. The Intel ICH3-S has internal 15 k Ω resistors. • 47 pF parallel capacitors may be placed as close to the USB connector as possible.
See MCH Hub Interface section of this checklist. PCI-X Interface Section 8.1 for complete list of topologies and lengths. ® • Group like signals together under the Intel • Refer to Section 12.9.1. P64H2 such as ground, 1.8 V, 3.3 V, etc. General Guidelines •...
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Layout Checklist Design Guide...
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Pentium M Processor and Intel E7501 Chipset Platform Schematics Schematics ® ® ® The following schematics for the Intel Pentium M processor/Intel E7501 chipset compatible platform Customer Reference Board (CRB) are included in this section. • System Block Diagram •...
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® ® ® Intel Pentium M Processor and Intel E7501 Chipset Platform Schematics • Power Connector and Power OK Circuit • CPUVCC Regulator • CK-408B • FWH, LPC Connector (Debug) • SIO, Legacy I/O • 1.2 V Regulation • LAN Controller and Connector •...
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