6 FDA Configuration
By default, the analog input is configured to use the balun input (AD1T-6T+) for both analog input channels, but
can be modified to utilize the onboard FDA (THS4541).
In terms of performance as compared with the balun input, SFDR is improves, but SNR performance degrades
by a few dBFS.
Figure 6-1. ADC3683EVM FDA Analog input (External Clocks, 65 MSPS)
This procedure shows how to configure the FDA single-ended to diferential conversion for CHA. The same
procedure can be performed for CHB (with the respective component designators).
The edge launched SMA connector J1 receives the single-ended analog input signal. R1 can be replaced with a
capacitor for AC coupling to FDA.
Modify the following components to complete path to FDA (located on top of EVM).
• Install: R1, R2, R14 (o ohm)
FDA Configuration
24
ADC368xEVM Evaluation Module
SBAU360 – DECEMBER 2020
Copyright © 2020 Texas Instruments Incorporated
