Datasheet

15
Figure 12. Recommended Power Supply Filter for HCPL-47XX Optocouplers.
RECOMMENDED V
CC
FILTER
8
0.1 µF
V
CC
10 µF
+
100 Ω
V
O
R
L
7
6
5
1
2
3
4
HCPL-4701 OR HCPL-4731
Figure 10. HCPL-47XX Isolated Monitoring Circuits for 2-Wire ISDN Telephone Line.
Figure 11. Typical Optical Isolation Used for Power-Loss Indication and Regulation Signal Feedback.
115/230
VAC
EMI FILTER
AND
CURRENT
LIMITER
ISOLATION
BARRIER
V
O
GND 2
1
12
12
SOFT START
COMMAND
INTERRUPT FLAG
POWER DOWN
POWER
SUPPLY
FILTER
CAPACITOR
SWITCHING
ELEMENT
RECTIFIER
AND
FILTER
CONTROL
CIRCUIT
ERROR
FEEDBACK
VIA CNR200
HCPL-4701
2-WIRE
ISDN
LINE
PROTECTION
CIRCUIT
P0WER
SUPPLY
SECONDARY
POWER
EMERGENCY
POWER
PRIMARY–SECONDARY
POWER ISOLATION
BARRIER
VAC
PRIMARY
TELEPHONE LINE
ISOLATION BARRIER
HCPL-4731
HCPL-4701
SWITCHED–
MODE
POWER
SUPPLY
RECEIVE
TRANSMIT
LINE POLARITY
LINE PRESENCE
SECONDARY/
EMERGENCY
POWER
V
CC
V
CC
– RETURN
TELEPHONE
LINE
INTERFACE
CIRCUIT
NOTE: THE CIRCUITS SHOWN IN THIS FIGURE REPRESENT POSSIBLE, FUNCTIONAL APPLICATION OF THE HCPL-47XX
OPTOCOUPLER TO AN ISDN LINE INTERFACE. THIS CIRCUIT ARRANGEMENT DOES NOT GUARANTEE COMPLIANCE,
CONFORMITY, OR ACCEPTANCE TO AN ISDN, OR OTHER TELECOMMUNICATION STANDARD, OR TO FCC OR TO OTHER
GOVERNMENTAL REGULATORY AGENCY REQUIREMENTS. THESE CIRCUITS ARE RECOMMENDATIONS THAT MAY MEET
THE NEEDS OF THESE APPLICATIONS. Agilent DOES NOT IMPLY, REPRESENT, NOR GUARANTEE THAT
THESE CIRCUIT ARRANGEMENTS ARE FREE FROM PATENT INFRINGEMENT.