Question about Capacitance to frequency conversion
Question about Capacitance to frequency conversion
(OP)
I am looking into converting 9pF to 22pF capacitance to frequency data. So I started doing research on Oscillator. I have area constraint since I am trying to do it on CMOS technology. The frequency can't be too high. preferable under 100kHz. Inductor is too big for CMOS and due to the low capacitance,low frequency and low area constraint, I am not sure what I should do.
I looked at normal RC oscillator and the Resistor needs to be in Mega ohms range if I want a low frequency. Does anyone has any suggestion?
I looked at normal RC oscillator and the Resistor needs to be in Mega ohms range if I want a low frequency. Does anyone has any suggestion?





RE: Question about Capacitance to frequency conversion
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Question about Capacitance to frequency conversion
RE: Question about Capacitance to frequency conversion
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Question about Capacitance to frequency conversion
RE: Question about Capacitance to frequency conversion
Consider using something like the CMOS 555 for the converter.
Remember that the C to F converter you are designing must be with the capacitor as you cannot have the wire leads in the picture.
Keith Cress
kcress - http://www.flaminsystems.com
RE: Question about Capacitance to frequency conversion
RE: Question about Capacitance to frequency conversion
htt
Then I'd start with the circuitry to measure the capacitance (High Frequency Bridge?) and use that value to drive some kind of FM oscillator (which could be all digital).