Voltage to Frequency Converter

[ravikarti]

V2F afterwards

Hi

I have built a small V2F converter based on AD654. I am getting a fairly linear variation of the frequency with voltage.

The purpose of my circuit is to display temperature from a NTC thermistor onto 2-7seg displays without use of ADC chip or a micro controller.

So i decided on V2F. Now i plan to give the frequency output of the V2F to 2-4bit counters. My requirement is in range of 5 to 50'C only. Can anyone help me with how to do other connections to the counter chip(4029).

I have given the V2F output to clock on units counter. When the units counter makes 1010 i reset it and increment the tens counter.

But if i leave the other pins, the counter will keep on counting...So i believe i have to enable the counter for a specific period of time only and disable otherwise. Can anyone help me in calculating this time

Or is there an easier way to do what i want to do(the bigger picture)?
ANy help is greatly appreciated.

thnx

 

[Ubergeek63]

Hi

I have built a small V2F converter based on AD654. I am getting a fairly linear variation of the frequency with voltage.

The purpose of my circuit is to display temperature from a NTC thermistor onto 2-7seg displays without use of ADC chip or a micro controller.

So i decided on V2F. Now i plan to give the frequency output of the V2F to 2-4bit counters. My requirement is in range of 5 to 50'C only. Can anyone help me with how to do other connections to the counter chip(4029).

I have given the V2F output to clock on units counter. When the units counter makes 1010 i reset it and increment the tens counter.

But if i leave the other pins, the counter will keep on counting...So i believe i have to enable the counter for a specific period of time only and disable otherwise. Can anyone help me in calculating this time

Or is there an easier way to do what i want to do(the bigger picture)?
ANy help is greatly appreciated.

thnx

https://www.electro-tech-online.com/custompdfs/2010/08/cd74hc390.pdf
https://www.electro-tech-online.com/custompdfs/2010/08/sn74hc574.pdf
https://www.st.com/stonline/books/pdf/docs/1981.pdf

 

[Reloadron]

You will need a counter gate circuit to gate and reset your counter chips or they will just count up non-stop without a reset. The attached should give you an idea. Also the power pins for the NAND are not shown. Anyway, this should give you an idea. I did not overly look at your counter.

Ron