What is the correct way to wire a piezoelectric circuit on a breadboard?

AI Thread Summary
The discussion revolves around difficulties in wiring a piezoelectric circuit on a breadboard to activate an LED using pressure. The user reports that the LED remains lit without pressure applied, indicating a potential wiring issue. Suggestions include ensuring a 1MΩ resistor is used and connecting the LED to pin 3 of the 555 timer instead of pin 5. Additionally, the output from the LM108 should be measured to verify if it can drive a power MOSFET. The conversation emphasizes checking wiring connections and component placements for proper functionality.
A31415
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Hi, I am having trouble implementing a circuit diagram onto a breadboard. The circuit involves a piezoelectric ceramic, which when pressure is applied, it should create enough power to activate 9V and light up an Led for a second. When I put the circuit together on the breadboard, to the best of my ability, the LED was already lit by the battery and nothing happened when pressure was applied to the piezo. Here is the link for the circuit diagram: http://circuitswiring.com/trigger-555-monostable-circuit-using-the-piezo-transducers/

I have attached the photos of the circuit below. What am I doing wrong?

Thanks!
 

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I cannot see the resistor from the piezoelectric ceramic to V+, but it has to be very large (at least 1MΩ). Here is a circuit diagram I found:
upload_2016-3-15_7-24-44.jpeg
 
I tried the 1M Ohm resister and the same issue occurred.

For the circuit you suggested. Where would the power, that I am using the piezoelectric to activate, connect?

Thanks!
 
A31415 said:
For the circuit you suggested. Where would the power, that I am using the piezoelectric to activate, connect?
The output pin (pin 6) of the LM108 has an amplified version of the signal from the transducer. Measure it and if it is large enough, use it to drive a power MOSFET or something.
 
A31415 said:
I tried the 1M Ohm resister and the same issue occurred.
Did you put it here ?

555piezo.jpg
 
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