sachinagg77
Member level 3
noise analysis switched-capacitor
I designed a switched capacitor PGA for gain settings of 0dB to 12dB.
To check the thermal/flicker noise contribution of this circuit, I used .NOISE analysis (spectre). The circuit was kept in closed loop. I would like to request for feedback on the following:
1) The noise summary indicates the "output noise power" and "input noise power". The "input noise power" should be "output noise power" divided by square of circuit gain. But, the results do not satisfy this relation.
2) When I simulate my circuit for gain settings other than 0dB, some of the switches are "OFF". These are bootstrapped switches. The noise summary indicates huge flicker noise coming from these "off switch" components.
Looking forward for comments and suggestions.
With Regards
Sachin
I designed a switched capacitor PGA for gain settings of 0dB to 12dB.
To check the thermal/flicker noise contribution of this circuit, I used .NOISE analysis (spectre). The circuit was kept in closed loop. I would like to request for feedback on the following:
1) The noise summary indicates the "output noise power" and "input noise power". The "input noise power" should be "output noise power" divided by square of circuit gain. But, the results do not satisfy this relation.
2) When I simulate my circuit for gain settings other than 0dB, some of the switches are "OFF". These are bootstrapped switches. The noise summary indicates huge flicker noise coming from these "off switch" components.
Looking forward for comments and suggestions.
With Regards
Sachin