madiger
Newbie level 5
I need to build a circuit that convert frequency into a voltage, and the LM2907 circuit on page 16 of the **broken link removed** seems to do the trick. The frequency range is 0 to 2.5kHz, and i want to maintain the linearity and response time, but the circuit in the datasheet doesnt produce a wide enough range of voltage. Would I be able to broaden the scale of the output voltage range if I ran the LM2907 output through an op amp?
I also thought about changing the Vcc value to 28VDC and changing the R1 value from 100K to 143K. Using the Vo formula they provide [Vo = Vcc * Fin * C1 * R1] it seems like i'd get an output voltage range from 0 to 10V at max frequency (2.5kHz). A wider range like this seems like it would produce results more accurately describing the frequency, but i dont want to lose the linearity or response time by changing the components too much.
i dont know, whats the best method?
I also thought about changing the Vcc value to 28VDC and changing the R1 value from 100K to 143K. Using the Vo formula they provide [Vo = Vcc * Fin * C1 * R1] it seems like i'd get an output voltage range from 0 to 10V at max frequency (2.5kHz). A wider range like this seems like it would produce results more accurately describing the frequency, but i dont want to lose the linearity or response time by changing the components too much.
i dont know, whats the best method?