Hello again ,
After some more research regarding PIR/photodiodes/piezoelectric sensors/etc. I've refined the requirements for the system.
Quick overview:
The device I'm building have 2 systems, one is an embedded circuit, and the second is, hopefully, will be a sensor that will trigger that embedded system to switch on.
The device itself will run on batteries (again hopefully for 3-6mo). In efforts to save power I'd like to turn on the embedded circuit only when an event happens and for that I need a sensor that will switch it on (maybe through a transistor).
The problem:
Again, in order to have the device run as long as possible (and w/o using 12 9V batteries , I've looked into piezoelectric sensors that can generate a 0-5V analog output for the switching. But, the bugs I'm interested in are about 4mg in weight, and I've yet to find a piezoelectric sensor that can detect such low force (corresponds to abt 4microNewtons I believe).
Perhaps a piezofilm? Or a resistor after the piezoelectric to boost the voltage?
Any comments/suggestions about making a sensitive & completely power source free switch will be very appreciated.
Furthermore, I've ran the numbers of running an average LED (IR~1.2V) on an average 9V battery and got anywhere from 20-100hrs depending on the resistor, additional time can be obtained using a voltage regulator (that will prevent the heat....). Though this is not enough, since I need it to run at least 3-6mo.
After some more research regarding PIR/photodiodes/piezoelectric sensors/etc. I've refined the requirements for the system.
Quick overview:
The device I'm building have 2 systems, one is an embedded circuit, and the second is, hopefully, will be a sensor that will trigger that embedded system to switch on.
The device itself will run on batteries (again hopefully for 3-6mo). In efforts to save power I'd like to turn on the embedded circuit only when an event happens and for that I need a sensor that will switch it on (maybe through a transistor).
The problem:
Again, in order to have the device run as long as possible (and w/o using 12 9V batteries , I've looked into piezoelectric sensors that can generate a 0-5V analog output for the switching. But, the bugs I'm interested in are about 4mg in weight, and I've yet to find a piezoelectric sensor that can detect such low force (corresponds to abt 4microNewtons I believe).
Perhaps a piezofilm? Or a resistor after the piezoelectric to boost the voltage?
Any comments/suggestions about making a sensitive & completely power source free switch will be very appreciated.
Furthermore, I've ran the numbers of running an average LED (IR~1.2V) on an average 9V battery and got anywhere from 20-100hrs depending on the resistor, additional time can be obtained using a voltage regulator (that will prevent the heat....). Though this is not enough, since I need it to run at least 3-6mo.