...or at least it appears to do so.
I put together a cross-coupled capacitor voltage doubler. When I have one DC source connected to M1 and M2 (to act as a single voltage rail) C2 exhibits an RC time constant. This should not be the case as it should immediately charge to the DC level once Vgs of M1 is above 3V.
I can fix this by connecting the drain of M2 to its own DC voltage source, V4. I can also ground the gate of M2 which eliminates M2 from the circuit; e.g, it never charges C1. A third way is to reduce the capacitances to <100pF and this delay goes away.
I don't get where the RC delay is coming from because there is no resistance! What gives? Some idiosyncrasy in the simulator?
Thanks.
I put together a cross-coupled capacitor voltage doubler. When I have one DC source connected to M1 and M2 (to act as a single voltage rail) C2 exhibits an RC time constant. This should not be the case as it should immediately charge to the DC level once Vgs of M1 is above 3V.
I can fix this by connecting the drain of M2 to its own DC voltage source, V4. I can also ground the gate of M2 which eliminates M2 from the circuit; e.g, it never charges C1. A third way is to reduce the capacitances to <100pF and this delay goes away.
I don't get where the RC delay is coming from because there is no resistance! What gives? Some idiosyncrasy in the simulator?
Thanks.
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