doubt in cmos oscillator design

[diaz080]

doubt in cmos rc oscillator design

from the papers i read cmos based rc oscillators are found to be stable with temperature variation and supply variation (around .5 % ) but the propagation delay of the inverter which is used was varying a lot with temperature Since frequency of oscillator is inversely related to propagation delay, how come the frequency is not varying across different temperature

 

[Audioguru]

If propagation delay affects the frequency of a high frequency oscillator made with ordinary slow Cmos inverters then increase the supply voltage to speed them up or use high speed Cmos (74HCxxxx).

 

[diaz080]

with temperature sweep frequency was not found to be varying here.but propagation delay was found varying.why is this so ? frequency and propagation delay are related,then why frequency is not varying with temperature sweep

 

[Audioguru]

What frequency?
What supply voltage?

 

[diaz080]

33khz supply 1.2v

 

[Audioguru]

A 1.2V supply is almost nothing.
The circuits I talked about are for NORMAL CD4xxx Cmos ICs in working circuits, not for custom-made ICs in wishful simulations.

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Like I said in your other thread about this fantasy circuit: OMG! The supply voltage is almost nothing.

 

[diaz080]

A 1.2V supply is almost nothing.
The circuits I talked about are for NORMAL CD4xxx Cmos ICs in working circuits, not for custom-made ICs in wishful simulations.

- - - Updated - - -

Like I said in your other thread about this fantasy circuit: OMG! The supply voltage is almost nothing.

tsmc 090 lib nmos and pmos are used here.