Temperature Compensated VCO follow up

[patchell]

    I managed to get the tempco down to 390ppM/C.  This is a triangle
VCO using an NPN/PNP pair to switch the current.  I was driving it at
about plus and minus 80mV before and changed that to plus and minus
100mV to get the improvement.  But, it looks like I will be forced to
try a saw tooth oscilator now.  Somehow, I suspect the current switch
(or OTA if that is how you want to look at it) is causing a lot of the
temp drift.

    Anybody have any experience concerning OTA's in triangle oscilators
and any tempco problems they might cause?

-Jim

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