HCNR200 Datasheet, PDF (15/19 Pages) Agilent(Hewlett-Packard) – High-Linearity Analog Optocouplers

+ILOOP
R1
10 kΩ
HCNR200
PD1
-ILOOP
R3
25 Ω
R2
10 kΩ
HCNR200
LED
R4
100 Ω
+ ^LM158
-
2N3906
0.001 µF
Z1
5.1 V
0.1 µF
HCNR200
PD2
2
Design Equations:
VOUT / ILOOP = K3 (R5 R3) / R1 + R3)
K3 = K2 / K1 = Constant = 1
Note:
The two OP-AMPS shown are two separate LM158, and not two channels in a single dual package,
otherwise the loop side and output side will not be properly isolated.
Figure 21. 4 to 20 mA HCNR200 receiver circuit.
0.001 µF
R5
80 kΩ
V_CC
5.5 V
-
+ _LM158
VOUT
Vcc
5.5V
R2
C1
150 Ω
1nF
R1
80k Ω
Vin
0.8V~4V
“0” @ 2200Hz
“1” @ 1200Hz
PD1/IC1
- _LM158 ^IC2
+
LED/IC1
HCNR200
Q1
2N3906
Q3
2N3904
R8
100kΩ
+I _LOOP
12V~40V
4 ~ 20mA
4mA (Vin=0.8V)
20mA(Vin=4V)
IC3
C3
LM158
R4 1nF
10k Ω C2
PD2/IC1
R3
10k Ω
5V1
Q4
R7
3k2Ω
Q2
2N3904
R6
150 Ω
R5
25 Ω
- I _LOOP
Design Equations:
(ILOOP/Vin)=K3(R5+R3)/(R5R1)
K3 = K2/K1 = Constant ≈ 1
Note:
The two OP-AMPS shown are two separate LM158 IC’s, and NOT dual channels in a
single package, otherwise, the LOOP side and input side will not be properly isolated;
The 5V1 Zener should be properly selected to ensure that it conducts at 187μA;
Figure 22. 4 to 20 mA HCNR200 transmitter circuit.
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