blueroomelectronics

Well as usual audioguru got me thinking about driving transistors to saturation. I've been using MOSFETs (sometimes incorrectly) and I have a problem that may or may not have a simple solution. I wanted to use a 2N7000 but it's only rated for 200ma continuous. I'd like to switch as close to the full 5V as possible for use with a GLCD display. I will see how bright a 2N4401 with its 0.7v drop will run both a 128x64LCD or a standard 2x16 LCD backlight. PS the PTC is getting uprated to 250ma (they open at twice their rating) PPS the Unicorn can be USB powered or Inchworm+ powered (up to 1A) http://www.blueroomelectronics.com/Unicorn.htm

Ahh thank you, I'll use the 2N4401 Do you know the 2N equivalent of the BC548 & BC558?

Ok is a 2N2222A a workable transistor? or a 2N4401?

I've got a Vgs of 20v on the datasheet, and a Vgs MAX of 4.0 on the same datasheet... http://www.aoc.nrao.edu/~pharden/ref/_IRF510.pdf Ahh, I see, the MAX 4V is the minimum it needs to switch on...

ROTFL free energy from coils, perpetual motion. Funny stuff. It's May 1st not April 1st...

It's not a working design. try switching something not lethal first. The gate has no point of reference. Also RS is not a great source of HV electronics. Is the 500V AC or DC? You need isolation between your 10V and the 500V like an optoisolator. 500V can mess up your day, life etc...

Should anyone not familiar with 500V electronics be playing with 500V?

On MOSFETs like the IRF510 which had an on resistance of 0.54 ohm won't even get warm at 350ma. No gate resistor is required and the PICs outputs will drive em fine at 5V. They are expensive though, much more than a 2N2222A + 680ohm resistor.