Table of Contents
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1.
General Description
This user guide describes how to set up and operate the LMK00308 evaluation module (EVM). The
LMK00308 is a 3-GHz, 8-output differential clock buffer intended for high frequency, low additive jitter clock
distribution and level translation. The EVM allows the user to verify the functionality and performance
specifications of the device. Refer to the LMK00308 datasheet for the functional description and
specifications.
2.
Features
Low-noise clock fan-out via two banks of four differential outputs and one LVCMOS output
Selectable differential output type (LVPECL, LVDS, HCSL, or Hi-Z)
3:1 input multiplexer with two universal input buffers and one crystal oscillator interface
DIP switch control of device configuration
3.3 V core and 3 independent 3.3 V/2.5 V output supplies (one per output bank) using external supply
inputs or optional LP3878-ADJ LDO or LMZ10500 switching regulator on board
AC- or DC-coupled input & output interface with low-skew, controlled-impedance traces and edge SMA
connectors
March 2012
Figure 1: LMK00308EVM Board Photo
SNAU117
LMK00308EVM User's Guide
LMK00308EVM User's Guide
User's Guide
March 2012
1
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Table of Contents
Related Manuals for Texas Instruments LMK00308EVM
Summary of Contents for Texas Instruments LMK00308EVM
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Page 1: General Description
3.3 V core and 3 independent 3.3 V/2.5 V output supplies (one per output bank) using external supply inputs or optional LP3878-ADJ LDO or LMZ10500 switching regulator on board AC- or DC-coupled input & output interface with low-skew, controlled-impedance traces and edge SMA connectors Figure 1: LMK00308EVM Board Photo LMK00308EVM User’s Guide March 2012 SNAU117... -
Page 2: Table Of Contents
Configuring OSCin for a Single Ended Input ............7 Clock Outputs ......................8 8.1. LVPECL and LVCMOS with 2.5 V Vcco ..............8 Schematics ......................... 9 Board Layout ......................12 Bill of Materials ...................... 16 LMK00308EVM User’s Guide March 2012... -
Page 3: List Of Figures
LIST OF FIGURES Figure 1: LMK00308EVM Board Photo ................1 Figure 2: LMK00308 Evaluation Board Quick Start Setup ..........4 Figure 3: Schematic Sheet #1 ..................9 Figure 4: Schematic Sheet #2 ..................10 Figure 5: Schematic Sheet #3 ..................11 Figure 6: Top Side, Layer #1 (Not to scale) .............. -
Page 4: Quick Setup
SMAs labeled CLKin0/0* or CLKin1/1*. By default, these differential inputs are AC coupled and terminated near the device with 100 ohms differential. To configure the EVM for a single-ended input, Clock Inputs refer to the section. LMK00308EVM User’s Guide March 2012... -
Page 5: Signal Path And Control Switches
Disabled/Hi-Z Table 4: Bank B Output Mode Selection Bank B Output Mode S1[1] CLKoutB_Type1 State S1[2] CLKoutB_Type0 State LVPECL LVDS HCSL Disabled/Hi-Z Table 5: REFout Enable Selection REFout Enable Mode S1[5] REFout_EN State Disabled/Hi-Z Enabled LMK00308EVM User’s Guide March 2012... -
Page 6: Power Supplies
Note: When the LMZ10500 switcher is used to power the DUT and an ultra-low-noise clock source is used, the higher output noise voltage of the switcher (compared to the LP3878-ADJ) can cause an slight increase LMK00308EVM User’s Guide March 2012... -
Page 7: Clock Inputs
To configure a single-ended clock input on OSCin, remove R34 and R37 to disconnect the crystal. Install 0.1 uF on C24 to provide an AC-coupled path from the SMA input labeled OSCin to the device input, which has internal biasing. Note that the OSCin path includes a 51-ohm termination on R42. LMK00308EVM User’s Guide March 2012... -
Page 8: Clock Outputs
When an output bank is configured for LVPECL and its Vcco supply is 2.5 V, it is suggested to replace the 160-ohm -termination resistor to ground with a lower value, such as 91 ohms, to maintain proper DC bias current on each output. LMK00308EVM User’s Guide March 2012... -
Page 9: Schematics
Schematics Figure 3: Schematic Sheet #1 LMK00308EVM User’s Guide March 2012... -
Page 10: Figure 4: Schematic Sheet #2
Figure 4: Schematic Sheet #2 LMK00308EVM User’s Guide March 2012... -
Page 11: Figure 5: Schematic Sheet #3
Figure 5: Schematic Sheet #3 LMK00308EVM User’s Guide March 2012... -
Page 12: Board Layout
10. Board Layout Figure 6: Top Side, Layer #1 (Not to scale) LMK00308EVM User’s Guide March 2012... -
Page 13: Figure 7: Internal Ground Plane, Layer #2 (Layer Inverted, Not To Scale)
Figure 7: Internal Ground Plane, Layer #2 (Layer Inverted, Not to scale) LMK00308EVM User’s Guide March 2012... -
Page 14: Figure 8: Internal Power Plane, Layer #3 (Not To Scale)
Figure 8: Internal Power Plane, Layer #3 (Not to scale) LMK00308EVM User’s Guide March 2012... -
Page 15: Figure 9: Bottom Side, Layer #4 (Top View, Not To Scale)
Figure 9: Bottom Side, Layer #4 (Top view, Not to scale) LMK00308EVM User’s Guide March 2012... -
Page 16: Bill Of Materials
Connector, SMT, End launch SMA 50 ohm Emerson 142-0701-806 CLKin0-, Network Power CLKin1+, CLKin1-, CLKoutA0+, CLKoutA0-, CLKoutA1+, CLKoutA1-, CLKoutA2+, CLKoutA2-, CLKoutA3+, CLKoutA3-, CLKoutB0+, CLKoutB0-, CLKoutB1+, CLKoutB1-, CLKoutB2+, CLKoutB2-, CLKoutB3+, CLKoutB3-, OSCin, REFout, REFout_EN, VCC_EXT, VCCO_EXT LMK00308EVM User’s Guide March 2012... - Page 17 IC DC-DC NANO MODULE LMZ10500SEE/NOPB Micropower 800mA Low Noise 'Ceramic National LP3878SD-ADJ Stable' Adjustable Voltage Regulator for 1V Semiconductor to 5V Applications, 8-pin LLP CRYSTAL 25.000 MHZ 18PF SMD Abracon ABLS-25.000MHZ-B4-F-T Corporation C10, C13, C15, C19, LMK00308EVM User’s Guide March 2012...
- Page 18 R10, R11, R12, R13, R14, R15, R16, R17 R19, R118, R124, R130 R21, R23, R25, R26, R29, R30, R32, R35, R39, R40 R43, R44 R131, R134, R145, R153 R146, R147, R148, R149, R150, R151, R152 LMK00308EVM User’s Guide March 2012...
- Page 19 Any exceptions to this is strictly prohibited and unauthorized by Texas Instruments unless user has obtained appropriate experimental/development licenses from local regulatory authorities, which is responsibility of user including its acceptable authorization.
- Page 20 REGULATORY COMPLIANCE INFORMATION (continued) FCC Interference Statement for Class B EVM devices This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications.
- Page 21 Also, please do not transfer this product, unless you give the same notice above to the transferee. Please note that if you could not follow the instructions above, you will be subject to penalties of Radio Law of Japan. Texas Instruments Japan Limited (address) 24-1, Nishi-Shinjuku 6 chome, Shinjukku-ku, Tokyo, Japan http://www.tij.co.jp...
- Page 22 FDA Class III or similar classification, then you must specifically notify TI of such intent and enter into a separate Assurance and Indemnity Agreement. Special Instructions. Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265 Copyright © 2012, Texas Instruments Incorporated...
- Page 23 NOTES...
- Page 24 TI products are designated by TI as compliant with ISO/TS 16949 requirements. Buyers acknowledge and agree that, if they use any non-designated products in automotive applications, TI will not be responsible for any failure to meet such requirements. Following are URLs where you can obtain information on other Texas Instruments products and application solutions: Products...
- Page 25 Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Texas Instruments LMK00308EVM/NOPB...