Texas Instruments ADS9218EVM-PDK, User Manual, Page: 6 / 29

2.2 ADC Differential Input Fully Differential Amplifier (FDA)
The THS4552 FDA is used to amplify the input signals applied to the SMA connector. The amplifier is a dual
configuration for the two different ADC channels. Each channel is configured with the same discreet feedback
components. The amplifier gain is set to 1 V/V and the bandwidth is set to 500 kHz for good performance up to
100 kHz. The
ADS9218 Power Optimized Signal Chain Circuit reference design covers component selection and
can help adjust component values for different optimizations.
Figure 2-2 shows a schematic of the FDA driver components.
GND
1
2 3 4 5
J3
GND
1
2 3 4 5
J4
GND
GND
AINP_A
AINM_A
10V
0.1µF
C10
5V
GND
25V
1000pF
C33
DNP
GND
GND
VCM_FDA
1.00k
R7
1.00k
R10
10.0
R6
10.0
R13
24.9
R8
24.9
R11
49.9
R32
DNP
49.9
R30
DNP
GND
50V
47pF
C11
50V
47pF
C13
100V
470pF
C12
3
1
2
VOCM1
4
14
15
V+
V-
13
16
THS4552IPWR
U6A
1.00k
R5
1.00k
R14
50V
270pF
C9
50V
270pF
C14
Figure 2-2. FDA Driver Schematic
Analog Interface www.ti.com
6 ADS9218EVM-PDK Evaluation Module SBAU409 – SEPTEMBER 2022
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated