Has anyone used the PIR sensor chip (and of course the associated PIR sensor they sell)

http://www.futurlec.com/M7612.shtml

The translation is somewhat unclear.  The length of time the output is on, can be varied using VR1 tied to pin 8 and thats clear...

TB is just how fast it will respond to a trigger ( I think)

However, if I want to have a timer setup such that it wont retrigger for a period of time, I'm thinking there isn't a timer built in for that, the only way to inhibit is to use the CDS input on pin 9, where I could trigger a 555 timer with the output, and feed a low going output to this pin.  The low pulse would need to be longer than the output pulse, since based on this from the datasheet

"If TRIAC or RELAY has already being triggered by PIR signal and turned into active mode , then CDS can not inhibit PIR again."

The end result of this is a motion detector to trigger a audio player, but need to delay from it triggering for a user settable time.  Sure I could do this with a 12F part, but client wants to build it cheap and no programming overhead.




      
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