AD4680/AD4681

Data Sheet

Rev. 0 | Page 8 of 29

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

12

11

10

1

3

49

2

NOTES

1. EXPOSED PAD. FOR CORRECT OPERATION OF THE DEVICE,

THE EXPOSED PAD MUST BE CONNECTED TO GROUND.

GND

REGCAP

CS

REFIO

GND

REFCAP

AD4680/AD4681

TOP VIEW

(Not to Scale)

Figure 8. Pin Configuration

Table 7. Pin Function Descriptions

Pin No.

Mnemonic

Description

1, 10

GND

Ground Reference Point. This pin is the ground reference point for all circuitry on the device.

2

Logic Interface Supply Voltage, 1.65 V to 3.6 V. Decouple this pin to GND with a 1 μF capacitor.

3

REGCAP

Decoupling Capacitor Pin for Voltage Output from Internal Regulator. Decouple this pin to GND with a

1 μF capacitor. The voltage at this pin is 1.9 V typical.

4

Power Supply Input Voltage, 3.0 V to 3.6 V. Decouple this pin to GND using a 1 μF capacitor.

5, 6

Analog Inputs of ADC B. These analog inputs form a differential pair.

7, 8

Analog Inputs of ADC A. These analog inputs form a differential pair.

9

REFCAP

Decoupling Capacitor Pin for Band Gap Reference. Decouple this pin to GND with a 0.1 μF capacitor. The

voltage at this pin is 2.5 V typical.

11

REFIO

Reference Input and Output. The on-chip reference of 2.5 V is available as an output on this pin for

external use if the device is configured accordingly. Alternatively, an external reference of 2.5 V to 3.3 V

can be input to this pin. Decoupling is required on this pin for both the internal and external reference

options. A 1 μF capacitor must be applied from this pin to GND.

12

CS

Chip Select Input. Active low, logic input. This input provides the dual function of initiating conversions on

the AD4680/AD4681 and framing the serial data transfer.

13

SDOA

Serial Data Output A. This pin functions as a serial data output pin to access the ADC A or ADC B

conversion results or data from any of the on-chip registers.

14

SDOB/ALERT

Serial Data Output B (SDOB). This pin functions as a serial data output to access the conversion results.

Alert Indication Output (ALERT). This pin operates as an alert going low to indicate that a conversion result

has exceeded a configured threshold.

This pin can operate as a serial data output pin or alert indication output.

15

SDI

Serial Data Input. This input provides the data written to the on-chip control registers.

16

SCLK

Serial Clock Input. This serial clock input is for data transfers to and from the ADC.

EPAD

Exposed Pad. For correct operation of the device, the exposed pad must be connected to ground.