Hi all,
I had construct a voltage to frequency converter using LM331. The circuit can be found in Figure 3 in the LM331 datasheet which you can found it at http://www.national.com/ds/LM/LM231.pdf
I use Proteus to simulate through the circuit and it works fine with a DC input signal (0-10V). But when i change my input signal to a pulse signal (square wave 0-10V), the output frequency i get is incorrect. Why is this happen? Is this means the VFC LM331 only accept DC input signal but not a square pulse signal? Or is because of my circuit connection got problem?
Also when i connect the circuit and test it in practical, i cant get output frequency from the oscilloscope. I had check through many times the circuit, and i am sure the connection is correct when i connect it in my breadboard. And yet i still dun understand why the VFC LM331 is not functioning in practical. Why is this happen? Please help me
I had construct a voltage to frequency converter using LM331. The circuit can be found in Figure 3 in the LM331 datasheet which you can found it at http://www.national.com/ds/LM/LM231.pdf
I use Proteus to simulate through the circuit and it works fine with a DC input signal (0-10V). But when i change my input signal to a pulse signal (square wave 0-10V), the output frequency i get is incorrect. Why is this happen? Is this means the VFC LM331 only accept DC input signal but not a square pulse signal? Or is because of my circuit connection got problem?
Also when i connect the circuit and test it in practical, i cant get output frequency from the oscilloscope. I had check through many times the circuit, and i am sure the connection is correct when i connect it in my breadboard. And yet i still dun understand why the VFC LM331 is not functioning in practical. Why is this happen? Please help me
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