SLAU150A December   2004  – October 2021 ADS7881 , ADS7891

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Features
    2. 1.2 Analog Interface
      1. 1.2.1 Signal Conditioning
      2. 1.2.2 Reference
    3. 1.3 Digital Interface
    4. 1.4 Power Supplies
  3. 2Using the EVM
  4. 3ADS78x1EVM Bill of Materials
  5. 4ADS78x1EVM Layout
  6. 5ADS78x1EVM Schematics
  7. 6Revision History

1.2 Analog Interface

The ADS7881 and ADS7891 ADCs have both a positive and negative analog input pin. The negative input pin, which has a range of –200 mV up to 200 mV is shorted on the board. A signal for the positive input pin can be applied at connector P1, pin 2 (as shown in Table 1-2) or at the center pin of the SMA connector J2.

Table 1-2 Analog Input Connector
Connector.Pin#(1) Signal Description
P1.2 +IN Noninverting input channel
P1.4 Reserved —
P1.6 Reserved —
P1.8 Reserved —
P1.10 Reserved —
P1.12 Reserved —
P1.14 Reserved —
P1.16 Reserved —
P1.18 Reserved —
P1.20 REF+ External reference input
(1) All odd-numbered pins of P1 are tied to AGND.