Relay Arc Supression Circuit



I have the following circuit:

+5Vdc
|
+---------------+------------------------+
| | |
| | |
330 Ohm Diode |
| | |
| | 5Vdc Relay Coil
| | |
LED 5.1V Zener |
| | |
| | |
| | |
+---------------+------------------------+
|
|
+---+---+
To Micro----1kohm--+B C |Transistor
| E |
+---+---+
|
|
|
GND


I'm concerned about reverse bias on the LED when the realy lets go. I
measure about 7.5 Vdc across the LED when the relay lets go. I think
the zener and the diode act as a good method to handle the coil
magnetic field collapse and ensure fast armature motion but I do
violoate the 5 Vdc LED reverse bias voltage. Any comments or
suggestions for this circuit? I need to maintain the LEDs for
visibility and troubleshooting. I'm hoping this thread discusses some
general techniques for realy arc supression and addresses the LED in
this specific example.

Thanks!

.



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