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Design >> Analog Design >> Beta multiplier with start up circuit-short channel design
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Message started by Analog2015 on Nov 28^th, 2015, 8:02am

Title: Beta multiplier with start up circuit-short channel design
Post by Analog2015 on Nov 28^th, 2015, 8:02am

How to get dimension of mosfets in start up circuit?
Also, I use equation

I_REF=2*(1-1/√K)^2/(R^2 KP_n W_1/L_1 )

for getting value of resistor R=717 ohm.
Iref=200uA, K=4, W/L=10/0.35, KP_n=170*10e-6.

For that equation i got very bad caracteristic of current. The value of current is bigger.
Maybe for short channel designe i must use some other equation???
Sheme and caracteristic are attached

Title: Re: Beta multiplier with start up circuit-short channel design
Post by raja.cedt on Nov 29^th, 2015, 12:23am

difficult to understand, can you please post ref schematic?

Thanks,
Raj.