Datasheet

AD650 Data Sheet
Rev. E | Page 6 of 20
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
V
OUT
1
+IN
2
–IN
3
BIBOLAR OFFSET
CURRENT
4
OFFSET NULL
14
OFFSET NULL
13
+V
S
12
ANALOG GND
11
–V
S
5
DIGITAL GND
10
ONE SHOT
CAPACITOR
6
COMPARATOR
INPUT
9
NC
7
F
OUTPUT
8
NC = NO CONNECT
AD650
TOP VIEW
(Not to Scale)
00797-010
Figure 2. D-14, N-14 Pin Configurations
1 20
192
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
–V
S
+V
S
NC
ANALOG GND
NC
DIGITAL GND
+IN
V
OUT
NC
OFFSET NULL
OFFSET
NULL
ONE SHOT
CAPACITOR
NC
NC
F
OUTPUT
COMPARATOR
INPUT
PIN 1
INDENTFIER
AD650
T
OP
VIEW
(Not to scale)
00797-011
Figure 3. P-20 Pin Configuration
Table 2. Pin Function Descriptions
Pin No.
D-14, N-14 P-20 Mnemonic Description
1 2 V
OUT
Output of Operational Amplifier. The operational amplifier, along with C
INT
,
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 –V
S
Negative Power Supply Input.
6 9 ONE-SHOT
CAPACITOR
The Capacitor, C
OS
, is Connected to This Pin. C
OS
determines the time period
for the one shot.
7 1, 5, 7, 10, 11, 15, 17 NC No Connect.
8 12 F
OUTPUT
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
+V
S
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.