ADG712 AD [Analog Devices], ADG712 Datasheet - Page 7

• Manufacturer Part Number: ADG712
• Description: CMOS Low Voltage 4 ohm Quad SPST Switches
• Manufacturer: AD [Analog Devices]

APPLICATIONS
Figure 9 illustrates a photodetector circuit with programmable
gain. An AD820 is used as the output operational amplifier.
With the resistor values shown in the circuit, and using different
combinations of the switches, gain in the range of 2 to 16 can be
achieved.
Test Circuits
REV. 0
(MSB) IN4
Figure 9. Photodetector Circuit with Programmable Gain
(LSB) IN1
D1
Test Circuit 1. On Resistance
IN2
IN3
+2.5V
V
S
V
V
S2
S1
V
IN
C1
S1
S2
S3
S4
S
R
ON
IN1, IN2
33k
R1
= V1/I
I
V1
GND
DS
+5V
V
0.1 F
DS
S
S2
S1
D
ADG713
D1
D2
D3
D4
GAIN RANGE 2 TO 16
GND
V
V
DD
DD
240k
120k
R4
R6
IN
D2
D1
0.1 F
120k
120k
120k
S
R10
R8
R9
240k
Test Circuit 5. Break-Before-Make Time Delay, t
120k
GND
V
R5
V
R
300
R7
DD
+5V
DD
L2
AD820
D
C
35pF
L2
Test Circuit 4. Switching Times
V
S
R
300
R2
510k
R3
510k
Test Circuit 2. Off Leakage
V
L
OUT2
I
S
(OFF)
A
V
+2.5V
OUT
C
35pF
L
R
300
S
L1
V
–7–
OUT
C
35pF
L1
D
I
V
D
V
OUT
V
V
(OFF)
OUT1
A
IN
IN
ADG712
ADG711
V
D
V
V
OUT1
OUT2
V
IN
V
t
50%
50%
ON
S
0V
0V
0V
ADG711/ADG712/ADG713
90%
90%
D
50%
t
Test Circuit 3. On Leakage
D
V
S
50%
50%
90%
90%
t
OFF
S
50%
t
D
90%
D
90%
I
D
(ON)
A
V
D