Opto-Electrical Ciruit Problem 1

[araz]

I have an opto-electrical circuit design using an optical transistor OP506A, and an Operational Amplifier TL072. When the Optical-eye is covered (no light goes to the optical eye), positive input (Pin 3) of the TL072 goes to +5V, then the output of the TL072 is triggered.

The Problem:
when the Optical eye is covered or darkened continuously (For Example: the device left "ON" in a dark room at night), the output trigger is repeated continuously. How could I prevent the continuous trigger of the out put? Could I change my Optical device to a one that trigger once? Any body has any idea?

I thank you all people in advance.

ARAZ

 

[jbartos]

Suggestion: Visit

http://www.angelfire.com/la/unisourcemarketing/

http://www.neumueller.com/optek/photosen.htm

http://www.optekinc.com/photosen.htm

http://focus.ti.com/docs/prod/productfolder.jhtml?genericPartNumber=TL072

http://members.nbci.com/Jon_Risch/catch-1.htm

http://www.ti.com/sc/docs/msp/tools/macromod.htm

for more info. Why is TL072, Dual Low-Noise JFET-Input General-Purpose Operational Amplifier applied? It has more complex internal circuitry. Would not a Single Low-Noise JFET do? Also, it may need a new optical transistor and to verify its characteristics in the design circuit.