Avago Technologies ACPL-224-500E - Manual (Page 42)

AV02-4387EN 39 Avago Technologies
Precision Isolation Amplifier for Unipolar Signals
Description
This circuit uses the HCNR200/1
High-Linearity Analog Optocoup ler
to achieve high accuracy and wide
dynamic range at a reason able cost.
This is accomplished by using low-
cost, precision op-amps with very
low input bias currents and offset
voltages. The circuit couples only
positive voltage analog signals.
Performance of Circuit
• DC to 10 kHz bandwidth
• Stable gain
• 0.1% nonlinearity
• 1 mV to 10 V input/output volt-
age range
Benefits
• Low­cost, high­accuracy solu tion
for coupling analog signals
• Easy availability of support circuit
components
• No offset adjustment is required
References
HCNR200/1 Technical Data
Alternative Avago Parts
1) HCPL-7800A, HCPL-7800, HCPL-
7840 Isolation Amplifier
2) HCPL-4562 Wideband Analog/
Video Optocoupler
3) HCPL-785X Hermetically Sealed
Isolation Amplifier
Analog Applications
–
+
PD1
2
3 A1
7
4
R1
200 k Ω
INPUT
BNC
1%
C3
0.1µF
V CC1 +15 V
C1
47 PF
LT1097
R6
6.8 k Ω
R4
2.2 k Ω
R5
270 Ω
Q1
2N3906
V EE1 -15 V
C4
0.1µF
R3
33 k Ω
LED
D1
1N4150
–
+
PD2
2
3
A2
7
4
C2
33 PF
OUTPUT
BNC
174 k Ω
LT1097
50 k Ω
1 %
V EE2 -15 V
C6
0.1µF
R2
C5
0.1µF
V CC2 +15 V
6 6
8
7
6
1
3
HCNR200/1
5
2
4
LED
NC
NC
PD1 PD2
K1 K2
ISOLATION
BARRIER