Datasheet

Independent Single-Supply Single-Ended Inverting Gain Stages
3-11
THS6043EVM Applications
3.9 Independent Single-Supply Single-Ended Inverting Gain Stages
Two independent inverting gain stages can be created by:
- Connecting the –V
CC
supply (J4) to GND (J5)
- Removing R7, R23, R24, and C3
- Addinging zero Ω jumpers at R4 and R14
- Installing 4.99 kΩ resistors at locations R20 and R21
- Jumpering pins 2 and 3 of JP1
- Adding gain resistors (Rg) at R3 and R15. Gain (Av) for each stage is
calculated by –Rf / Rg (−R5 / R3 and –R16 / R15).
Figure 3−9. Independent Single−Ended Single−Supply Inverting Gain Configuration
R18
R3
R5
R16
1
J4
−VCC
TP1
+
C9
R1
R17
49.9
W
R12
49.9
W
+V
J5
GND
J2
IN2
TP3
J1
IN1
−V
−
+
U1A
THS6043
2
3
1
14
4
R21
J6
OUT1
+V
Z1
0
+V
JP1
J3
+VCC
J7
OUT2
R15
>>> GND
Z2
0
R14
0
R4
0
FB2
−
+
U1B
THS6043
12
11
13
TP4
OUT2
>>> GND
FB1
TP2
OUT1
R20
49.9 W
4.99 kW
4.99 kW
1 mF
750 W
750 W
49.9 W
3.10 Shutdown Operation (Channels 1 and 2)
The output of channels 1 and 2 can both be shut down simultaneously
when a voltage above 2 Vdc is applied to the shutdown input (JP2 on the
EVM—see Figure 3−10). In shutdown mode, the output goes to ground.
Normal operation is restored for voltages below 0.8 V on the shutdown
(SD) input.
When no jumper is installed in position JP2, the SD input is pulled to
ground through R26. When a jumper is installed in position JP2, a voltage