This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

LM231: 100kHz Scale?

Part Number: LM231

Hi Team,

I have following request, i think answer is no but can you please confirm? Also do you think we have alternative device that can fit?

"

I will only use lm231 as IC, I have a question to ask you here. It is written on the product's datasheet that it can make a 10 kHz scale de frequency to voltage converter. Could this scale be 100 kHz?

"

Thanks in advance

Best Regards

Furkan Sefiloglu

  • 100 kHz is possible with the LM231 as shown in figure 7 of the datasheet; see section 9.2.2 for the necessary changes for high-speed operation.

  • Hi Furkan,

    it should be noted that many of the datasheet specifications refer to the voltage-to-frequency conversion and not to the frequency-to-voltage conversion.

    This appnote mentions that a frequency-to-voltage conversion up to 100kHz is possible, but that the conversion at 100kHz suffers from a heavily increased temperature drift:

    snoa734b.pdf

    It should also be noted that the frequency-to-voltage conversion needs a proper square wave input signal with clean and steep edges.

    A good way to circumvent these issues is to put a frequency divider at the input of LM231 and to divide the input frequency by a factor of 10 or so. The symmetrical square wave output signal of this frequency divider will be able to properly drive the LM231 then. But don't forget the recommended C-R differentiator between the frequency divider output and the input of LM231.

    Kai 

  • Thank you Kai for resolving this issue. I will close this thread now.