Impathy
New Member
Hi, I have a simple circuit using a Piezo Transducer to turn on an LED and it works fine. Squeeze the disc and the light gets brighter the harder you squeeze.
(Sorry, didn't know the diagram for a piezo transducer )
The voltage drops signifigantly after the transducer. (On a 9v it drops down to about 1.2v. Even with a 12v that's not turning on a light) So I tried setting it up with a simple comparator to make the transducer act as a switch (with the comparator - LM393) There are plenty of other ways to make it as a switch using low voltage to turn on the main 12v current. But here is my problem:
I want the end current to be directly proportional to the voltage output of the transducer as such:
The transducer outputs 0v... I want the light to output 0v
The transducer outputs 1.5v... I want the light to output 12v
Is there any part that can achieve this that I have not discovered?
If there is such thing as a voltage variable resistor, I'd be set. A resistor with 3 leads. A, B &C. Current runs from A to B light a normal resistor. It cuts down the voltage and such. But - if C is connected to a seperate current, it could work as a dynamic variable resistor dependant on a small voltage applied to it (0 - 1.5v) could be directly proportional to the ohms (47k ohms - 0 ohms). That would work for me if such part existed. Here's a simple picture if that didn't work for you.
If there is any easy way to get my 1.5v signal to switch, amplify, change resistance or anything - to my main 12v current. Please let me know. Thanks in advance, Sorry if this is a silly question, I couldn't find an answer.
-Andy
(Sorry, didn't know the diagram for a piezo transducer )
The voltage drops signifigantly after the transducer. (On a 9v it drops down to about 1.2v. Even with a 12v that's not turning on a light) So I tried setting it up with a simple comparator to make the transducer act as a switch (with the comparator - LM393) There are plenty of other ways to make it as a switch using low voltage to turn on the main 12v current. But here is my problem:
I want the end current to be directly proportional to the voltage output of the transducer as such:
The transducer outputs 0v... I want the light to output 0v
The transducer outputs 1.5v... I want the light to output 12v
Is there any part that can achieve this that I have not discovered?
If there is such thing as a voltage variable resistor, I'd be set. A resistor with 3 leads. A, B &C. Current runs from A to B light a normal resistor. It cuts down the voltage and such. But - if C is connected to a seperate current, it could work as a dynamic variable resistor dependant on a small voltage applied to it (0 - 1.5v) could be directly proportional to the ohms (47k ohms - 0 ohms). That would work for me if such part existed. Here's a simple picture if that didn't work for you.
If there is any easy way to get my 1.5v signal to switch, amplify, change resistance or anything - to my main 12v current. Please let me know. Thanks in advance, Sorry if this is a silly question, I couldn't find an answer.
-Andy
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