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Design >> Analog Design >> Startup time in bandgap refernces
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Message started by analogy on Feb 7^th, 2017, 12:29pm

Title: Startup time in bandgap refernces
Post by analogy on Feb 7^th, 2017, 12:29pm

What should be the rise-time of a bandgap circuit with an enable pin? Should I be worried if for certain rise times to the enable pin of a bandgap reference I see bizarre startup behavior?

Let me know if I need to further clarify my question.
Thanks.

Title: Re: Startup time in bandgap refernces
Post by tzg6sa on Feb 11^th, 2017, 11:51am

Bizarre is never good. It tells you that there is something unintended.

Otherwise the settling requirement depends on the applciation and the circuitry connected to the bandgap. Can't be said anything in general. Ask your tutor/boss about it.

Title: Re: Startup time in bandgap refernces
Post by analogy on Feb 11^th, 2017, 12:06pm

Thank you tzg6sa!

Quote:

Otherwise the settling requirement depends on the applciation and the circuitry connected to the bandgap

Could you elaborate on some of the applications based on your experiences? Let's say that you have a bandgap reference - now do you directly connect bandgap output to current mirrors? And if so, do you have to worry about sink/source circuit's impedance (and that impedance affecting start-up response of bandgap)?

Title: Re: Startup time in bandgap refernces
Post by tzg6sa on Feb 16^th, 2017, 4:15am

You should know what you are doing and why you are doing so. No one designs a circuit without any idea how it will be used later.