[time-nuts] Linear voltage regulator hints...

Bob Camp kb8tq at n1k.org
Mon Dec 8 19:48:00 EST 2014


Hopefully the issue  (and question) is about stability of the EFC voltage. Any decent OCXO should have a voltage stability that’s well below it’s temperature stability when run off of a fairly standard regulator. As an example, An OCXO that does 5x10^-9 over 0 to 70 C probably has a voltage stability below 5x10^-10 for a 1% change. One percent is more than what a modern regulator should be moving when running an OCXO.   


> On Dec 8, 2014, at 7:33 PM, Dave M <dgminala at mediacombb.net> wrote:
> Dan Kemppainen wrote:
>> Hi,
>> In playing with some oscillators and a GPSDO here, I think I'm seeing
>> a voltage sensitivity issue.
>> So, I started looking at the output voltage of various regulators vs.
>> temp. Using standard LM/UA type linear regulators and some LDO's, they
>> all appear to be pretty sensitive to temperature. (millivolt / few
>> degrees Fahrenheit sort of sensitivity). Most of the datasheets seem
>> to ignore temp sensitivity. Almost like they are so bad they don't
>> want to publish it...
>> Does anyone have hints on TO-220 or D-Pak type regulators that have
>> really good temp coefficients and good line regulation? A few PPM/Deg
>> C might be nice, if possible. Or am I into a 'roll you own' type
>> design...
>> Dan
> Yes, in order to get low PPM stability, you are going to "roll your own". No 3-terminal regulator or reference that I know of can run an OXCO (heater and oscillator).
> What are your voltage and current requirements?
> Dave M 
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.

More information about the time-nuts mailing list