DG309B Datasheet, PDF (6/8 Pages) Vishay Siliconix – Improved Quad CMOS Analog Switches

DG308B/309B
Vishay Siliconix
TEST CIRCUITS
+15 V
C
V_S
R_g = 50 W
0V, 15 V
V+
S
D
IN
GND
V–
C
V_S
Off Isolation = 20 log
V_O
–15 V
FIGURE 3. Off Isolation
+15 V
V+
R_g
S
D
V_g
IN
12 V
GND
V–
–15 V
C
+15 V
V_O
50 W
V+
V_S
S₁
D₁
R_g = 50 W
IN₁
0V, 15 V
S₂
D₂
NC
0V, 15 V
IN₂
GND
C = RF bypass
V_S
X_TALK Isolation = 20 log
V_O
V–
C
–15 V
50 W
V_O
50 W
FIGURE 4. Channel-to-Channel Crosstalk
V_O
C_L
1000 pF
V_O
IN_X ON
DV_O
OFF
ON
DV_O = measured voltage error due to charge injection
The charge injection in coulombs is Q = C_L x DV_O
FIGURE 5. Charge Injection
APPLICATIONS
V_IN1
+5 V
V_L
+15 V
V+
V_IN2
CH
GND
DG419
V–
30 pF
+15 V
+
LM101A
–
–15 V
Gain =
R_F + R_G
R_G
–15 V
Gain 1 (x1)
Gain 2 (x10)
Gain 3 (x100)
Gain 4 (x1000)
Logic High = Switch On
DG308B
V–
–15 V
+15 V
R_F1
18 kW
R_F1
9.9 kW
R_F1
100 kW
R_G1
2 kW
R_G2
100 W
R_G3
100 W
GND
FIGURE 6. A Precision Amplifier with Digitally Programmable Inputs and Gains
www.vishay.com S FaxBack 408-970-5600
4-6
Document Number: 70047
S-52896—Rev. E, 14-Jul-97