Texas Instruments ADS7042EVM-PDK, Руководство пользователя

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2 Introduction to the ADS704X-5XEVM
Each ADS704X-5XEVM board includes the peripheral analog circuits and components required to extract
optimum performance from each ADC signal chain. Important portions of the EVM are highlighted in
Figure
2-1 , and described in the subsequent sections.
Figure 2-1. Important Subsections of the ADS704X-5XEVM
2.1 Analog Inputs
As shown in Figure 2-1 , the ADS704X-5XEVM has two analog input paths: a single-ended input path highlighted
in red, and a differential input path highlighted in green. SMA connectors and headers are included on each path
to connect external signals. These signals feed into a driver amplifier and then to one of two ADC footprints,
where the digital output is supplied to the PHI via J4.
2.1.1 Single-Ended Input Path
The single-ended input path consists of an inverting driver amplifier, an RC circuit, and two ADC footprints.
Figure 2-2 shows the single-ended input path schematic.
1
2
3
4
5
6
OPA836IDBVR
U6
EVM_DVDD
AGND
0
R12
0
R11
49.9 R18
49.9 R20
49.9 R19 SDO_A
SCLK_AB
CS_A
AGND
AGND
AVDD
OPA_VDD
OPA_VSS
0 R37
DNP
AGND
JP1
AGND
U3_AINM
U3_AVDD
U3_DVDD
U3_SCLK
U3_SDO
U3_CS
U3_AVDD
U3_DVDD
U3_SCLK
U3_SDO
U3_CS
U3_AINP
U3_AINM
AGND
U3_AINP
0
R40
AINM
1.00k
R36
1.00k
R35
CS
4
SDO
3
SCLK
2
DVDD
1
GND
8
AVDD
7
AINP
6
AINM
5
ADS7042IDCUR
U3
AGND
100
R42
VBIAS
CS
1
SDO
2
SCLK
3
DVDD
4
GND
5
AVDD
6
AINP
7
AINM
8
ADS7042IRUGR
U8
DNP
1
2 3 4 5
J1
100nF C12
DNP
100nF
C10
10nF
C14
1µF
C8
1µF
C9
16.0
R14
16.0
R38
300pF
C11
Replace R43 and R44 with 100nF
capacitors when OPA_VSS ≠ AGND
0
R43
Figure 2-2. Single-Ended Input Path on the ADS704X-5XEVM
www.ti.com Introduction to the ADS704X-5XEVM
SBAU382 – NOVEMBER 2021
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ADS7042EVM-PDK, ADS7049-Q1EVM-PDK, and ADS7057EVM-PDK
Evaluation Module
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