Caspar
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Hi all,
I've designed a current mirror circuit (attached) for constant gm biasing. Things work as expected when I simulate the circuit in its own cell; I get the correct operating point and my 10 uA current. However, when I introduce this block into another (more complex) schematic, doing the same (DC) analysis produces 'different' results! (all devices turn off). Strangely enough, copying the circuit as a schematic (so not a symbol) doesn't help either. I haven't connected it to any terminals in the big circuit yet, to exclude some freak loading problem.
I know the circuit can operate in multiple states, but I thought that's why the startup device is there. I've also tried putting caps with initial voltage values, no succes. Model libraries, supply voltages etcetera are all the same. Reopening cadence or the ADE doens't help, nor does copying cellviews. I'm actually running two DC analyses on the same circuit, getting different results... :s
Any ideas? Thanks in advance...
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