AD7794/AD7795

Rev. D | Page 12 of 36

Pin No.

Mnemonic

Description

18

AIN4(−)/REFIN2(−)

Analog Input/Negative Reference Input. AIN4(−) is the negative terminal of the differential analog input pair

AIN4(+)/AIN4(−). This pin also functions as the negative reference input for REFIN2. This reference input can

19

PSW

Low-Side Power Switch to GND.

20

GND

Ground Reference Point.

21

Supply Voltage, 2.7 V to 5.25 V.

22

23

DOUT/RDY

Serial Data Output/Data Ready Output. DOUT/RDY serves a dual purpose. It functions as a serial data output

pin to access the output shift register of the ADC. The output shift register can contain data from any of the

on-chip data or control registers. In addition, DOUT/RDY operates as a data ready pin, going low to indicate

the completion of a conversion. If the data is not read after the conversion, the pin goes high before the

next update occurs. The DOUT/RDY falling edge can also be used as an interrupt to a processor, indicating

that valid data is available. With an external serial clock, the data can be read using the DOUT/RDY pin. With

CS low, the data/control word information is placed on the DOUT/RDY pin on the SCLK falling edge and is

valid on the SCLK rising edge.

24

DIN

Serial Data Input to the Input Shift Register on the ADC. Data in this shift register is transferred to the control

registers within the ADC with the register selection bits of the communications register identifying the

appropriate register.