Message forwarded on behalf of Forrest Christian Original attachment was too large ( > 30k) Can be seen here =A0 =A0 =A0 =A0 =A0 =A0 http://bit.ly/MOSFET_Driver_250nS From:=A0Forrest Christian To:=A0"Microcontroller discussion list - Public." Date:=A0Fri, 12 Aug 2011 06:27:42 -0600 Subject:=A0Re: [EE] Sizing MOSFET gate resistors Amazingly simple driver circuit is attached. Short version: =A0Treat the level-shift transistor as an =A0inverting amplifier, not a switch. =A0 =A0And to whoever recommended LTspice - THANK YOU! =A0Finally a spice that actually seems to work for me. Thanks for the pointers on the fet app notes. =A0 I had found AN-937 but had missed that part of it... =A0trying to skim documents for useful data sometimes causes that to happen for me. I think I keep coming back to this - dv/dt of the FQB22P10 seems to -6 v/ns. =A0 I don't think I'm slewing anything even close to this rate. Input, or output. =A0 0 to 30V would be about 5ns, and I'm taking much longer than that to switch.. more in the dozens of ns category. Still, I'm feeling that that 10 ohm resistor is good CYA engineering... -forrest --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .