Preliminary Technical Data

AD7625

Rev. PrB | Page 7 of 11

Pin No.

Mnemonic

Description

18

VDD2

P

Analog 2.5V Supply.

19, 20

VDD1

P

Analog 5V supply. Isolate from Pin 1 with a ferrite bead.

21

VCM

AO

Common Mode Output.

When using any reference scheme, this pin produces ½ of the voltage present on the REF pin which can

be useful for driving the common mode of the input amplifiers.

22

IN-

AI

Differential Negative Analog Input.

Referenced to and must be driven 180° out of phase with IN+.

23

IN+

AI

Differential Positive Analog Input.

Referenced to and must be driven 180° out of phase with IN-.

24

GND

P

Ground.

25, 26,

28

CAP2

AO

Connect all three pins to a single 10uF X5R capacitor with the shortest distance. The other side of the

capacitor must be placed close to pin 27 (GND).

27

GND

P

Ground.

Return path for 10uF capacitor connected to pins 25, 26, and 28.

29, 30,

32

REF

AI/O

Buffered Reference Voltage.

When using the internal reference or 1.2V external reference (REFIN input), the 4.096V system reference

is produced at this pin.

disabled.

In either case, connect all three pins to a single 10uF X5R capacitor with the shortest distance. The other

side of the capacitor must be placed close to pin 31 (GND)

31

GND

P

Ground.

Return path for 10uF capacitor connected to pins 29, 30, and 32.