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Simulators >> Circuit Simulators >> Start-up check @bandgap reference using spectre
https://designers-guide.org/forum/YaBB.pl?num=1080282799

Message started by eddy on Mar 25^th, 2004, 10:33pm

Title: Start-up check @bandgap reference using spectre
Post by eddy on Mar 25^th, 2004, 10:33pm

Hi all;

I'd like to simulate start-up in CMOS BGR(Bandgap reference) using spectre.

Unfortunately, I don't know how to do method for this.

I want to simulate tran. for VDD(0 ~1.8V) and node condtion: 0).

If anybody knows this, let me know.

Thank you.

Title: Re: Start-up check @bandgap reference using spectr
Post by fastsim on Apr 9^th, 2004, 2:39pm

Sweep vdd source from 0 to 1.8.
set IC to '0.0'v on the diode-connected BJTs collector nodes. (assuming you are using vertical PNP in N-Well process.)

If you are using Cadence schematic composer and Analog Design
Environmnet ( Analog Artist), you can set up from from GUI.

Actually, you probably also want to try set vdd to 1.8, but use
IC to set the collector voltages to 0.0v so as to force a false
operating points at the beginning of transient to see if the circuit
will settle to the right solution.

If you ramp you VDD from 0, the transient operating points for all
the nodes should all close to 0. You may not be able to find the
start-up problem while there is a real problem.