View Full Version : Interfacing Reed Switch and Relays

11-09-2011, 01:01 PM
I am making a project on 8051 in which ill be taking inputs to 8051 uC using reed switches and providing outputs through relays.
I am not able to understand how to interface reed switches with the controller. I dont think i should connect it directly.
The contact resistance of reed switch will be around 80 mOhms. Also for relays ill have to use darlington arrays as far as i have researched. But how do we buy relays?
I might be switching a AC line and controlling using the microcontroller which will be provinding DC signal.
Any help appreciated.

11-10-2011, 02:54 PM
Ohkay. This is what i have come up with. Please let me know if you find any problems with the circuit.

http://img6.imageshack.us/img6/6356/crkt.jpg (http://imageshack.us/photo/my-images/6/crkt.jpg/)

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