AD6644

Rev. D | Page 8 of 24

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

DNC = DO NOT CONNECT

PIN 1

IDENTIFIER

AD6644

TOP VIEW

(Not to Scale)

1

2

GND

3

4

GND

5

ENCODE

6

ENCODE

7

GND

8

9

10

GND

11

14

AIN

12

AIN

13

GND

15 16 17 18 19 20 21 22 23 24 25 26

27

GND

28

29

GND

30

31

DNC

32

OVR

33

34

GND

35

DMID

36

D0 (LSB)

37

40

D1

38

D2

39

D3

41

42

43

44

45

46

47

48

49

50

51

52

Figure 3. Pin Configuration

Table 8. Pin Function Descriptions

Pin Number

Mnemonic

Description

1, 33, 43

3.3 V Power Supply (Digital), Output Stage Only.

2, 4, 7, 10, 13, 15, 17, 19, 21, 23, 25, 27, 29,

34, 42

GND

Ground.

3

2.4 V (Analog Reference). Bypass to ground with 0.1 μF microwave chip

capacitor.

5

ENCODE

Encode Input. Conversion initiated on rising edge.

6

ENCODE

Complement of ENCODE. Differential input.

8, 9, 14, 16, 18, 22, 26, 28, 30

5 V Analog Power Supply.

11

AIN

Analog Input.

12

AIN

Complement of AIN. Differential analog input.

20

C1

Internal Voltage Reference. Bypass to ground with 0.1 μF microwave chip

capacitor.

24

C2

Internal Voltage Reference. Bypass to ground with 0.1 μF microwave chip

capacitor.

31

DNC

Do not connect this pin.

32

OVR

Overrange Bit. High indicates analog input exceeds ±FS.

35

DMID

36

D0 (LSB)

Digital Output Bit (Least Significant Bit). Twos complement.

37 to 41, 44 to 50

D1 to D5, D6 to

D12

Digital Output Bits in Twos Complement.

51

D13 (MSB)

Digital Output Bit (Most Significant Bit). Twos complement.

52

DRY

Data Ready Output.