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EVM Headers, Test Points, and Configuration
52
SLOU489 – August 2017
Copyright © 2017, Texas Instruments Incorporated
Hardware Configuration
Figure 62. AFE EVM ADC Clock Source Configuration Schematic
Figure 63. EVM ADC Clock Source Configuration Examples
Configuration 1:
To use the onboard single-ended crystal oscillator as the clock source for the AFE,
connect shunt jumpers for configuration 1 (as seen in
). Note: J41 powers the onboard oscillator
with 3.3 V, due to the power limitations of the FXO-HC735-40 low-jitter crystal oscillator. The
recommended ADC clock input for new designs is to use low-jitter square signals (LVCMOS levels, 1.8-V
amplitude).
Configuration 2 (LVDS Only):
To use a direct external clock as the clock source for the AFE, connect
shunt jumpers for configuration 2 (as seen in
). Connect a single-ended external clock generator
to SMA J39. Set the clock source to an appropriate frequency, such as 10 MHz to 100 MHz, and +13-dBm
amplitude.