[time-nuts] Designing and building an OCXO and GPSDO

[Mark Sims]

For your temperature sensor and/or ADC consider the Analog Devices AD537 voltage to frequency converter chip.  It has an onboard temperature sensor or could be interfaced to a thermistor, etc.  The on chip sensor has a fairly large thermal mass.  If you need instantaneous response to temperature use a very small thermistor.  

Since the output is frequency,  any time nut worth his/her/its salt should be able to come up with a suitable counter circuit.  One system that I did had the V/F freq set around 200 Hz.  Counting a 16 MHz clock over 256 cycles of V/F waveform yielded microdegree resolution.  
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