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® Intel 80331 I/O Processor Design Guide March 2005 Order Number:273823-003...
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States and other countries. The ARM* and ARM Powered logo marks (the ARM marks) are trademarks of ARM, Ltd., and Intel uses these marks under license from ARM, Ltd.î *Other names and brands may be claimed as the property of others.
This is required only for unbuffered clocks and was already mentioned in the previous row. Table 51: removed row in “Trace Length: 80331 signal Ball to Series Termination” because the series termination is no longer needed. October 2004...
Designers please note that this guide focuses upon specific design considerations for the 80331 and is not intended to be an all-inclusive list of all good design practices. Use this guide as a starting point and use empirical data to optimize your particular design.
Intel® 80331 I/O Processor Design Guide Introduction 1.1.1 Terminology and Definitions Table 1. Terminology and Definitions (Sheet 1 of 2) Term Definition ® 80331 Intel 80331 I/O processor Stripline in a PCB is composed of the conductor inserted in a dielectric with GND planes to the top and bottom.
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Outbound At or toward the PCI interface of the 80331 ATU from the Internal Bus. Inbound At or toward the Internal Bus of the 80331 from the PCI interface of the ATU. ® Local processor Intel XScale core within the 80331 ®...
Introduction ® About the Intel 80331 I/O Processor ® The 80331 is a multi-function device that integrates the Intel XScale core (ARM* architecture compliant) with intelligent peripherals and PCI-to-PCI Bridge. The 80331 consolidates the following into a single system: ®...
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Intel® 80331 I/O Processor Design Guide Introduction Figure 1 provides a block diagram of the 80331. ® Figure 1. Intel 80331 I/O Processor Functional Block Diagram 16-bit UART 2 - 1²C 32/64-bit DDR ® Intel XScale™ Units Units Interface Core...
Intel® 80331 I/O Processor Design Guide Package Information Package Information The 80331 is offered in a Flip Chip Ball Grid Array (FCBGA) package. This is a full-array package with 829 ball connections. The mechanical dimensions for this package are provided in the figure below and...
Intel® 80331 I/O Processor Design Guide Package Information Power Plane Layout Figure 5 provides an example of how the 80331 DDR, CPU core and 1.5 V core power planes are ® partitioned on the Intel IQ80331 Evaluation Platform Board (IQ80331).
Intel 80331 I/O Processor Applications This section provides a block diagram of a 80331 Serial ATA adapter card application. This entire SATA RAID card adapter can be implemented with just a few chips using the 80331 integrated PCI-X bridge and IO processing capability.
Intel® 80331 I/O Processor Design Guide Terminations Terminations This chapter provides the recommended pull-up and pull-down terminations for a 80331 layout. Table 3 lists these 80331 termination values. On a motherboard, the PCI Local Bus Specification, Revision 2.3 requires that the PCI signals provide the termination resistors. Pull-ups on the PCI signals are not required with PCIODT_EN = 1 (enabled), because they are implemented on the die.
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S_ACK64#, S_FRAME#, S_IRDY#, S_DEVSEL#, S_TRDY#, S_STOP#, S_PERR#, S_LOCK#, S_M66EN, S_SERR# and XINT[3:0]# NOTE: This signal is muxed onto signal A[20]. Primary PCI-X Bus Width: By default, identifies 80331 subsystem as 64-bit unless user attaches appropriate pull-down resistor. 1.5 K pull-down when P_32BITPCI# 0 = 32 bit wide bus.
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133 MHz PCI-X: use 0.01 µF to GND. Private Memory Enable: PRIVMEM latched at rising (deasserting) edge of P_RST# and determines when the 80331 operates with Private Memory Space on the secondary PCI bus of the PCI-to-PCI 1.5 K pull-down when Bridge.
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0 = Hold in reset. (Requires pull-down resistor.) 1 = Do not hold in reset. (Default mode) Muxed onto signal AD[5] Bridge Enable: BRG_EN latched at rising (deasserting) edge of P_RST# and determines when the 80331 operates with PCI-to-PCI Bridge. 1.5 K pull-down when BRG_EN 0 = Disable Bridge, enable P_CLK input on S_CLKIN input.
Intel® 80331 I/O Processor Design Guide Terminations Analog Filters The following section describes filters needed for biasing PLL circuitry. 3.1.1 Pin Requirements CCPLL To reduce clock skew, the V balls for the Phase Lock Loop (PLL) circuit are isolated on the CCPLL package.
Terminations DDR Resistor Compensation Figure 8 provides the 80331 DDR II DDRES circuitry. The DDRRES1 resistor has a tight tolerance of 40.2 ohm 0.5%. DDRRES2 is used as compensation for DDR-II OCD. Due to the fact that OCD is not supported this pin should be pulled to GND with a 1K resistor.
Intel® 80331 I/O Processor Design Guide Terminations DDR Driver Compensation External reference resistors are used to control slew rate and driver impedance. The DDRIMPCRES (or DDRDRVCRES) resistor directly controls the on-die termination (ODT). The recommendations are as follows: • DDRIMPCRES: controls on-die termination, DDR - 385 ohms, DDRII - 285 ohms. Note that the closest standard 1% resistors are acceptable •...
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Intel® 80331 I/O Processor Design Guide Terminations This Page Intentionally Left Blank...
In fact, it is highly recommended that the board design be simulated to determine optimum layout for signal integrity. The information in this chapter provides guidelines to aid the designer with board layout. Several factors influence the signal integrity of a 80331 design. These factors include: •...
Intel® 80331 I/O Processor Design Guide Routing Guidelines Crosstalk Crosstalk is caused by capacitive and inductive coupling between signals. Crosstalk is composed of both backward and forward crosstalk components. Backward crosstalk creates an induced signal on victim network that propagates in the opposite direction of the aggressor signal. Forward crosstalk creates a signal that propagates in the same direction as the aggressor signal.
Intel® 80331 I/O Processor Design Guide Routing Guidelines EMI Considerations It is highly recommended that good EMI design practices be followed when designing with the 80331. • To minimize EMI on your PCB a useful technique is to not extend the power planes to the edge of the board.
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Intel® 80331 I/O Processor Design Guide Routing Guidelines Table 4. Decoupling Recommendations Number of Voltage Plane Voltage Pins Package C (µF) Caps DDR/DDRII 2.5/1.8V VCC25/18 1210 DDR/DDRII 2.5/1.8V VCC25/18 7343 Core 1.5V VCC15 0603 Core 1.5V VCC15 1210 1.35V VCC13 0603 1.35V...
Intel® 80331 I/O Processor Design Guide Routing Guidelines Trace Impedance All signal layers require controlled impedance of 50 Ω +/- 15%, microstrip or stripline where appropriate for motherboard applications and 60 Ω +/- 15%, microstrip or stripline, for add-in card applications.
Motherboard Stack Up Information When 80331 is used in server and workstation Raid On Mother Board (ROMB) applications the motherboard is implemented on eight layers. The specified impedance range for all board implementations are 50 ohms +/-15%. Adjustments are made for interfaces specified at other impedances.
Intel® 80331 I/O Processor Design Guide Board Layout Guidelines Table 5. Motherboard Stack Up, Stripline and Microstrip (Sheet 2 of 2) Nominal Minimum Maximum Variable Type Notes (mils) (mils) (mils) Stripline Microstrip 15.0 Each interface sets the trace spacing based on its signal integrity of differential impedance requirements.
Board Layout Guidelines Adapter Card Stackup The 80331 can be implemented on PCI-X adapter cards with six or eight layer stackups. The specified impedance range for all adapter card implementations are 60ohms +/-15%. Adjustments are made for interfaces specified at other impedances.
Interrupt Routing and IDSEL Lines Figure 14 shows the 80331 connected to three PCI connectors. Notice that the interrupts are rotated for each connector. The practice of Rotating INTs can also be used when connecting to individual multifunction PCI devices as well. The IDSEL lines acts as chip selects during the configuration cycles.
6.1.1 PCI Arbitration 80331 contains two PCI Arbiters to facilitate arbitration on the primary and secondary PCI buses. Refer to the PCI Local Bus Specification, Revision 2.3, for more information on arbiter algorithms. The specification essentially states that the algorithm needs to be fair to prevent any one device from consuming to much of the PCI bandwidth.
Intel® 80331 I/O Processor Design Guide PCI-X Layout Guidelines PCI General Layout Guidelines For acceptable signal integrity with bus speeds up to 133 MHz it is important to PCB design layout to have controlled impedance. • Signal trace velocity needs to be roughly 150 – 190 ps/inch •...
Intel® 80331 I/O Processor Design Guide PCI-X Layout Guidelines ® Intel 80331 I/O Processor PCI/X Layout Analysis The following sections describe layout recommendations based on the signal integrity simulation analysis. This analysis was conducted using the following parameters: • System board stack up: 50 ohm +/- 15% single-ended impedance •...
The recommended clock buffer layout are specified as follows: • Match each of the 80331 output clock lengths to within 25 mils to help minimize the skew. • Keep distance between clock lines and other signals “d” at least 25 mils from each other.
CLKOUT to CLKIN) should be routed 3.5” longer than the Clocks running to the Slots. This should be done to a tolerance of within 25 mills. Total Length of 80331 PCI CLKs on a Less than 14.0” maximum. motherboard (or embedded design).
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Intel® 80331 I/O Processor Design Guide PCI-X Layout Guidelines Table 8. PCI-X Clock Layout Requirements Summary (Sheet 2 of 2) Parameter Routing Guidelines Maximum skew for PCI. 1.0 ns. Point-to-point signal routing needs to be used to keep reflections Routing Guideline 1.
6.4.2 Single-Slot at 133 MHz Figure 17 shows one of the chipset PCI AD lines connected through TL_AD1 line segments to a single-slot connector CONN1 through TL1 line segment to the 80331. Figure 17. Single-Slot Point-to-Point Topology CONN1 Table 9.
Intel® 80331 I/O Processor Design Guide PCI-X Layout Guidelines 6.4.3 Embedded PCI-X 133 MHz This section lists the routing recommendations for PCI-X 133 MHz without a slot. Figure 18 shows the block diagram of this topology and Table 10 describes the routing recommendations.
Intel® 80331 I/O Processor Design Guide PCI-X Layout Guidelines 6.4.4 Embedded PCI-X 133 MHz Alternate Topology This section lists another embedded topology with routing recommendations for PCI-X 133 MHz. Figure 19 shows the block diagram of this topology and Table 11 describes the routing recommendations.
Intel® 80331 I/O Processor Design Guide PCI-X Layout Guidelines 6.4.5 Combination of PCI-X 133 MHz Slot and Embedded Topology Figure 20and Table 12 combine the two topologies using both a slot and an embedded device. Figure 20. Embedded PCI-X 133 MHz Topology CONN1 Table 12.
Microstrip Trace Spacing 15 mils, from edge to edge Spacing from other groups: 25 mils minimum Group Spacing edge-to-edge Trace Length 1 TL1: From 80331 signal Ball to first 1.0” minimum - 7.0” 1.0” minimum - 7.0” maximum connector maximum Trace Length TL2 between connectors 0.8”...
Table 22. PCI 66 MHz Embedded Table (Sheet 2 of 2) Parameter Routing Guideline for AD Bus Trace Length 1 TL1: From 80331 signal Ball to first 5.0” maximum junction Trace Length TL2 between junctions 0.5” minimum - 3.5” maximum Trace Length TL_EM1 to TL_EM4 from junction to 2.0”...
Microstrip Trace Spacing 15 mils, from edge to edge Group Spacing Spacing from other groups: 25 mils minimum edge-to-edge Trace Length 1 TL1: From 80331 signal Ball to first 1.0” minimum to 5.0” maximum 1.0” minimum - 4.5” maximum connector Trace Length TL_EM1, TL_EM2: From 1st PCI 1.5”...
Intel® 80331 I/O Processor Design Guide PCI-X Layout Guidelines Table 25. PCI 33 MHz Embedded Routing Recommendations (Sheet 2 of 2) Group Spacing Spacing from other groups: 25 mils minimum edge-to-edge Trace Length 1 TL1: From 80331 signal Ball to first 4.5”...
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PCI 33 MHz Mixed Mode Routing Recommendations (Sheet 2 of 2) Routing Guideline for lower AD Routing Guideline for Parameter upper AD Bus Trace Length 1 TL1: 80331 signal Ball to 1st 1.0” minimum - 5.5” 1.0” minimum - 5.5” maximum junction maximum Trace Length TL2 from 1st junction to 1st PCI 1.5 - 4.0”...
External memory can be configured as host addressable memory or private 80331memory utilizing the Address Translation Unit and Bridge. DDR Bias Voltages The 80331 supports 2.5 V DDR memory and 1.8V for DDRII. Table 27 lists the minimum/maximum values for the DDR memory bias voltages and...
80331 with the DDR-SDRAM memory sub-system needs continuous ground referencing for all DDR signals. The DDR channel requires the referencing stack-up to allow ground referencing on all of the DDR signals from the 80331 to the parallel termination at the end of the channel. Note: Leave unused M_CKs and M_CK#s unconnected.
Intel® 80331 I/O Processor Design Guide Memory Controller 7.3.1 DDR 333 Stackup Example Table 31 below provides an example of a table of recommended topologies for motherboard and add-in card eight layer PCB designs. Figure 35 provides an example of a cross section used to implement 100 ohm differential trace impedance.Throughout this section the important...
CB, data mask DM, and DQS associated strobe. The 80331 source synchronous signals are divided into groups consisting of data bits DQ and check bits CB. There is an associated strobe DQS for each DQ, DM and CB group. When data masking is not used system memory DM pins on the DDR needs to be tied to ground.
Intel® 80331 I/O Processor Design Guide Memory Controller Figure 38. DIMM DQ/DQS Topology V T T 5 1 o h m s + /- 5 % T L 4 T L 1 T L 2 T L 3 2 2 o h m s + /- 5 %...
The 80331 drives the command clock in the center of the valid window, and the source-clocked signals propagate with the command clock signal. An important timing specification is the difference between the command clock flight time and the source clocked signal flight time.
Intel® 80331 I/O Processor Design Guide Memory Controller 7.4.2.1 Control Signals Termination The control signal group includes RAS#, CAS#, WE#, BA[1:0], MA[12:0] CS[1:0]# , and CKE[1:0]. The series and parallel termination is shown in Table Table 43. Source Clocked Signal Routing...
Intel® 80331 I/O Processor Design Guide Memory Controller Table 44. Control Signals Routing Guidelines Parameter Routing Guideline Route over unbroken ground plane is preferred. Reference Plane (Refer to Table for alternatives if this is not feasible). Micro-strip only for Un-buffered memory...
Intel® 80331 I/O Processor Design Guide Memory Controller 7.4.3 Embedded Configuration The following tables provide layout guidelines for applications in which the DDR 333 memory SDRAM components are placed directly on the board without a DIMM. 7.4.3.1 DDR 333 Source Synchronous Routine Guidelines This section lists the recommendations for the DDR 333 embedded source synchronous routing.
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Intel® 80331 I/O Processor Design Guide Memory Controller Table 46. DDR 333 Embedded Source Synchronous Routing Recommendations (Sheet 2 of 2) Parameter Routing Guideline 51 ohms +/- 5% • Place the VTT terminations in VTT island after the DIMM (trace length of 0.15” to 0.5”).
Intel® 80331 I/O Processor Design Guide Memory Controller 7.4.3.3 DDR 333 Embedded Address/Command/Control Routing Guidelines This section lists the recommendations for the DDR 333 embedded address/command/control signal routing (RAS#, CAS#, WE#, BA[1:0], MA[12:0] CS[1:0]# CKE[1:0]). Refer to Table 51 Figure 47 for a block diagram of the lengths and matching requirements.
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Intel® 80331 I/O Processor Design Guide Memory Controller Table 51. DDR 333 Embedded Address/Command Routing Recommendations (Sheet 2 of 2) Parameter Routing Guideline • The package lengths from Die to Ball provided in Table 37 must be accounted for when length matching •...
Intel® 80331 I/O Processor Design Guide Memory Controller DDR II 400 Layout Guidelines This section lists the DDRII layout guidelines for both DIMM and embedded designs. The topologies that were analyzed include registered DIMM (RawA and RawB configurations) and embedded single bank configurations (both ECC and Non-ECC type).
Clock Target Differential Impedance 100 ohms and 50 ohms single-ended impedance • One Die Termination - ODT value of 75Ω was assumed for all DDR II simulations. • Memory Model Micron U26 and Intel generic models • PLL Clock - ICS ICSU877 •...
Intel® 80331 I/O Processor Design Guide Memory Controller 7.5.2 DDRII-400 Trace Width/Impedance Requirements Table 57 below provides an example of a table of recommended topologies for motherboard and add-in card eight layer PCB designs. Throughout this section the important recommendation to meet is the trace impedance.
Table 58 for a block diagram of the lengths and matching requirements. ® Figure 49. Intel 80331 I/O Processor DDRII 400 DIMM Source Synchronous Routing DQ Group 1 Y1 +/- 50 mils 8 lines DQS Group 1 DQS# Group 1...
• Spacing from other DQ groups 20 mils minimum • For DQS from any other signals: 20 mils minimum Overall Trace Length: 80331 signal Ball to DIMM 2” minimum to 8” maximum (correlated with the clock connector (no series connector) length from ball to DIMM).
> 20 mils between other signals. 2.0”min to 10.0” max correlated within the +/- 1.0” of Trace Length 1:80331signal Ball to DIMM connector the DQ/DQS and command signal length (from 80331 to DIMM connector). Length Matching: • Within differential clock signals +/- 0.0250”...
Trace Impedance 45 ohms +/- 15% or 50 ohms +/- 15% 2.0”min to 10” max (Correlated with in +/- 1” of Trace Length: Overall length from 80331 signal Ball to DQ/DQS and command lead-in MB length) DIMM Connector Refer to following table for segment lengths.
Intel® 80331 I/O Processor Design Guide Memory Controller 7.5.4 Embedded Configuration The following tables provide layout guidelines for applications in which the DDRII 400 memory SDRAM, registers and PLL components are placed directly on the board without a DIMM. 7.5.4.1 DDRII 400 Embedded Source Synchronous Routine Guidelines This section lists the recommendations for the DDR II 400 embedded source synchronous routing.
Intel® 80331 I/O Processor Design Guide Memory Controller 7.5.4.2 DDRII 400 Embedded Clock Routing Recommendations This section lists the recommendations for the DDR II 400 clock signals. Refer to Figure 57 Table 68 for a description of the segment lengths and matching requirements...
• >12 mils within group • >20 mils from any other clock/DQ/DQS groups. 2” minimum - 10” maximum length matched within +/- Overall length 80331 signal Ball to register input 1.0” of target motherboard clock M_CK to PLL. Series Termination none •...
Intel® 80331 I/O Processor Design Guide Memory Controller DDR Signal Termination This section provides suggested guidelines for layout of the DDR termination resistors: • Place a 1.25 V termination plane for DDR or a 0.9V termination plane for DDR II 400 on the top layer or one of the inner layers, just beyond the DIMM connector for DDR.
Intel® 80331 I/O Processor Design Guide Memory Controller DDR Termination Voltage The V DDR termination voltage must track the V and provide the termination voltage to the termination resistors. This tracking must be 50 percent of (V ) over voltage, temperature, and noise.
The Peripheral Bus Interface Unit (PBI) is a data communication path to Flash memory components and peripherals of a 80331 hardware system. The PBI allows the processor to read and write data to these supported flash components and other peripherals. To perform these tasks at high bandwidth, the bus features a burst transfer capability which allows successive 8- or 16-bit data transfers.
Intel® 80331 I/O Processor Design Guide Peripheral Local Bus 8.1.3 Bus Width Each address range attributes are programmed in the PBIs boundary registers. The PBI allows an 8-, or 16-bit data bus width for each range. The PBI places 8- and 16-bit data on low-order data signals, simplifying the interface to narrow bus external devices.
Intel® 80331 I/O Processor Design Guide Peripheral Local Bus 8.1.4 Flash Memory Support PBI peripheral bus interface supports 8-, or 16- bit Flash devices. The PBI provides programmable wait state functionality for peripheral memory windows. Note: Potentially, programmable wait state functionality could be connected to any peripheral device that has a deterministic wait state profile.
Intel® 80331 I/O Processor Design Guide Peripheral Local Bus 8.1.5 Layout Guidelines for the Peripheral Bus This section provides basic layout guidelines for using the Peripheral Bus. Figures below provide the topology for simulation of clock, control and data lines.
Intel® 80331 I/O Processor Design Guide Peripheral Local Bus Topology Layout Guidelines This section provides the topologies for routing the Address/Data bus for single load, latched single load and dual load latched topologies. Note that no length matching is required between the AD lines.
Intel® 80331 I/O Processor Design Guide Peripheral Local Bus Figure 65. Peripheral Bus Latched Bidirectional Single Load Topology Flash T L1 Latch Table 74. Routing Guideline Latched Bidirectional Latch Single Load Parameter Routing Guidelines Route over unbroken ground plane or power plane. If...
0.9V Power Sequencing The 80331 requires that the VCC33 voltage rail be powered up first and then the VCC15. Note that there are no sequence order requirements for the VCC25 or VCC18 rail. The power down sequence is the same in the reverse order.
This proposal makes specific assumptions about the system behavior during a power failure. When the below assumptions are not guaranteed, it is the responsibility of the vendor to ensure them. P_RST# is asserted to 80331 when there is at least 2 µs of reliable power remaining. This is •...
Intel® 80331 I/O Processor Design Guide Power Delivery In order to trigger a power fail sequence while the IOP power is still valid operating range, a comparator circuit such as the one shown in Figure 67 is recommended. Figure 67.
CKE[1:0] are low. CKE signals will stay low providing the DDR voltage is not removed from 80331. If 80331 is isolated from the DDR battery voltage it is recommended that the CKE circuit shown in Figure 68 be implemented.
For applications not supporting battery back-up, this circuit not required. When so, follow these steps: • Pull DDR CKE pins high and leave CKE signals on 80331 as ‘no connects’. This keeps SDRAM from entering a pseudo, self-refresh mode, which can cause a lock-up condition on the SDRAM device.
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IQ80331 Evaluation Platform Board ® The Intel IQ80331 Evaluation Platform Board (80331), also known as the evaluation board, is implemented as a add-in card. This section provides an overview of the IQ80331 features and describes the circuits specific to the IQ80331.
Intel® 80331 I/O Processor Design Guide JTAG Circuitry for Debug JTAG Circuitry for Debug ® Certain restrictions exist in order to use JTAG based debuggers with the Intel XScale microarchitecture. This is primarily due to the Tap Controller reset requirements of the Intel ® XScale microarchitecture and the reset requirements of specific JTAG debuggers.
Intel® 80331 I/O Processor Design Guide JTAG Circuitry for Debug 11.3 System Requirements In order to successfully invoke a debug session, the JTAG debug unit must be able to control nTRST and nSRST independently. The nTRST signal allows the debugger to get the TAP controller in a known state.
11.4 JTAG Hardware Requirements ® Due to the conflicting requirements of Multi-ICE* and the Intel XScale microarchitecture, it is necessary to incorporate a circuit that can drive TRST# low at power up and weakly pull it high at all other times. The following section details the circuits required for the Macraigor Raven*, WindRiver Systems* visionPROBE* / visionICE*, and ARM* Multi-ICE*.
Intel® 80331 I/O Processor Design Guide Debug Connectors and Logic Analyzer Connectivity Debug Connectors and Logic Analyzer Connectivity 12.1 Probing PCI-X Signals To ease the probing and debug of the PCI-X signals it is recommended to passively probe the PCI-X bus signals with a logic analyzer. This can be accomplished by placing six AMP...
Intel® 80331 I/O Processor Design Guide Debug Connectors and Logic Analyzer Connectivity Table 83. Logic Analyzer Pod 6 Mictor-38 Pin Number Even Pod Logic Analyzer Channel Number PCI-X Signal Name CLK/16 Unused AD63 AD62 AD60 AD59 AD58 AD57 AD56 AD55...
PCI Special Interest Group “Terminating Differential Signals on PCBs” , Steve Kaufer, Kelee Crisafulli, Printed Circuit Design, March 1999 Intel documentation is available from your local Intel Sales Representative or Intel Literature Sales. To obtain Intel literature write to or call:...
Intel® 80331 I/O Processor Design Guide References 13.2 Electronic Information Table 86. Electronic Information The Intel World-Wide Web (WWW) Location: http://www.intel.com Customer Support (US and Canada): 800-628-8686...
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