AD7170

Rev. 0 | Page 7 of 16

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

1

SCLK

2

DOUT/RDY

3

AIN(+)

4

AIN(–)

5

REFIN(+)

10 NC

9 PDRST

7GND

6REFIN(–)

AD7170

TOP VIEW

(Not to Scale)

NOTES

1. NC = NO CONNECT.

2. CONNECT EXPOSED PAD TO GROUND.

Figure 5. Pin Configuration

Table 5. Pin Function Descriptions

Pin No.

Mnemonic

Description

1

SCLK

Serial Clock Input. This serial clock input is for data transfers from the ADC. The SCLK has a Schmitt-triggered

input. The serial clock can be continuous with all data transmitted in a constant train of pulses. Alternatively, it

can be a noncontinuous clock with the information being transmitted from the ADC in smaller batches of data.

2

DOUT/RDY

Serial Data Output/Data Ready Output. DOUT/RDY serves a dual purpose. DOUT/RDY operates as a data ready

pin, going low to indicate the completion of a conversion. In addition, it functions as a serial data output pin to

access the data register of the ADC. Eight status bits accompany each data read. See

for further details.

The DOUT/

Figure 13

RDY falling edge can be used as an interrupt to a processor, indicating that new data is available. If

the data is not read after the conversion, the pin goes high before the next update occurs.

3

AIN(+)

Analog Input. AIN(+) is the positive terminal of the differential analog input pair AIN(+)/AIN(−).

4

AIN(−)

Analog Input. AIN(−) is the negative terminal of the differential analog input pair AIN(+)/AIN(−).

5

REFIN(+)

Positive Reference Input. An external reference can be applied between REFIN(+) and REFIN(–). The nominal

6

REFIN(−)

Negative Reference Input.

7

GND

Ground Reference Point.

8

Supply Voltage, 2.7 V to 5.25 V.

9

PDRST

Power-Down/Reset. When this pin is low, the ADC is placed in power-down mode. All the logic on the chip is

reset, and the DOUT/RDY pin is tristated. When PDRST is high, the ADC is taken out of power-down mode. The

on-chip clock powers up and settles, and the ADC continuously converts. The internal clock requires 1 ms

approximately to power up.

10

NC

This pin should be connected to GND for correct operation.

EPAD

Connect the exposed pad to ground.