bootstrap capacitor for IR2111 driver + Mosfet B25NM60N

Thread Starter

julius64

Joined Jun 17, 2008
6
Hi:
I need solved a next problem: My drivers IR2111 dont work fine, and I to know what bootstrap capacitor is necesary for driver IR2111 with a MOSFET B25NM60N 600V, 20A. If you know something this, you can need help about this?, Or please give me equation for calculating the value of Bootstrap capacitor.
Very thank
 

thingmaker3

Joined May 16, 2005
5,073
Cboot > (Qg + Dmax*Tsw*Idrv ) / ΔV

Where:
Qg is the gate charge of the MOSFET
Dmax is the maximum duty-cycle​
Tsw is the switching period​
Idrv is the average consumption of the driver​
ΔV is the ripple you accept across the bootstrap capacitor​
 
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