CAMALEAO
Full Member level 4
Hi guys,
I am trying to measure the output and the input resistance of a current mirror.
Currently I am applying a vdc voltage at the output to set the operating point and then an AC voltage source with 1VAC. After simulating I compute V/I.
I am getting around 80Gohm. Is this normal? 5V devices, 130nm, vdd 3.8V, 500nA.
Is this correct? Is there any other method to measure the output resistance? Maybe I can use a current source at the output with 1A AC, but how do I set the operating point?
Finally I read somewhere that we can measure Iout at Vout_min and Vout_max and compute R(ac) using V/I. For this I need to do the simulation in DC?
Finally, is there any logic in simulating the output resistance DC? Because in the books we read output resistance, and in simulation if we use an AC voltage source we are measuring the impedance.
Regards.
I am trying to measure the output and the input resistance of a current mirror.
Currently I am applying a vdc voltage at the output to set the operating point and then an AC voltage source with 1VAC. After simulating I compute V/I.
I am getting around 80Gohm. Is this normal? 5V devices, 130nm, vdd 3.8V, 500nA.
Is this correct? Is there any other method to measure the output resistance? Maybe I can use a current source at the output with 1A AC, but how do I set the operating point?
Finally I read somewhere that we can measure Iout at Vout_min and Vout_max and compute R(ac) using V/I. For this I need to do the simulation in DC?
Finally, is there any logic in simulating the output resistance DC? Because in the books we read output resistance, and in simulation if we use an AC voltage source we are measuring the impedance.
Regards.
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