AD650

Data Sheet

Rev. E | Page 6 of 20

PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS

+IN

2

–IN

3

BIBOLAR OFFSET

CURRENT

4

OFFSET NULL

14

OFFSET NULL

13

12

ANALOG GND

11

DIGITAL GND

10

ONE SHOT

CAPACITOR

6

COMPARATOR

INPUT

9

NC

7

8

NC = NO CONNECT

AD650

TOP VIEW

(Not to Scale)

Figure 2. D-14, N-14 Pin Configurations

1

20

19

2

3

4

5

6

7

8

18

17

16

15

14

9

10

11

12

13

NC = NO CONNECT

–IN

NC

BIPOLAR OFFSET

CURRENT

NC

NC

ANALOG GND

NC

DIGITAL GND

PIN 1

INDENTFIER

AD650

TOP VIEW

(Not to scale)

Figure 3. P-20 Pin Configuration

Table 2. Pin Function Descriptions

Pin No.

D-14, N-14

P-20

Mnemonic

Description

1

2

is used in the integrate stage of the V to F conversion.

2

3

+IN

Positive Analog Input.

3

4

–IN

Negative Analog Input.

4

6

BIPOLAR OFFSET

CURRENT

On-Chip Current Source. This can be used in conjunction with an external

resistor to remove the operational amplifier’s offset.

5

8

Negative Power Supply Input.

6

9

ONE-SHOT

CAPACITOR

for the one shot.

7

1, 5, 7, 10, 11, 15, 17

NC

No Connect.

8

12

Frequency Output from AD650.

9

13

COMPARATOR INPUT

Input to Comparator. When the input voltage reaches −0.6 V, the one shot is

triggered.

10

14

DIGITAL GND

Digital Ground.

11

16

ANALOG GND

Analog Ground.

12

18

Positive Power Supply Input.

13, 14

19, 20

OFFSET NULL

Offset Null Pins. Using an external potentiometer, the offset of the

operational amplifier can be removed.