Hi, i need a voltage controlled oscillator and reading in my textbook there is an example how to make one using a frequency to voltage converter. They use a LM331 IC and i have attached the circuit the textbook shows.
I have a LM2907 frequency to voltage converter and would like to use this instead of the LM331 (which i dont have). (The LM2907 datasheet doesnt have a VCO example so i cant follow that) Is it ok to use this instead of the LM311 in its circuit?
Assuming it is, i'm unsure of what pins on the LM2907 correspond to the pins on the LM331 VCO circuit.
I have the 14 pin LM2907N
My guess so far at the pins are:
LM331 pins = LM2907 pins
1 3
2 11
3 5
4 12
5 4
6 2
7 10
8 8
To be honest these really are just guesses, i don't understand the workings of either the LM331 or LM2907 sufficiently to make a proper guess and suspect i can't use the LM2907 to replace the LM331.
The LM331 is a voltage to frequency converter. The LM2907 is Frequency to voltage converter. In the LM331 it outputs a frequency based on a voltage (note, in data sheet the 331 can also be used a FV conv.). The LM2907 outputs a voltage based on frequency input.
I bought the lm2907 instead of the lm331 because it was cheaper, from farnell.
I've learnt my lesson i guess. The CD4046 sounds like a good option as i can get one from my local electronics store unlike the lm331 which i'd have to order online.
I went and got a 4046, works a treat. Much simpler to use than i was expecting too. 1 resistor and 1 capacitor to get a VCO from 0Hz to upto 2Mhz with 10v Vdd amazing!
I went and got a 4046, works a treat. Much simpler to use than i was expecting too. 1 resistor and 1 capacitor to get a VCO from 0Hz to upto 2Mhz with 10v Vdd amazing!
actually i havnt been over 20khz yet, and i was quoting the philips datasheet i have which says minimun 1 Mhz typical 2Mhz at Vdd = 10v although i'm not confident i havnt misread it!