Tuesday, January 6, 2009

PWM-Based Current Controller

A friend was looking for ways to control current flow in one of his projects. As always, MacGyver was approached to find a solution for him. So, MacGyver did just that. Pictured below is a PIC-based, PWM current controller that runs at 70kHz with 0-100% duty cycle varied via the multiturn trimpot. The MOSFET used is supposed to be able to handle about 50A with 0.022ohms on resistance. I don't think it can hit that high without exploding with the current heatsink.

Anyhow, the whole purpose of this board is to ascertain how much current does his project needs. From there, an alternative circuit will be made to cater just for that requirement... No need for fancy PIC, LED and all... That's for later... :-)

2 comments:

M.Zaifful said...

salam,basir, bleh let me know what purpose for this project, i want to know about it,maybe it would be useful someday, Impressive, it may drain power as high 50Ampere.Thanks

Basir Atan said...

Salam Zaifful,

It's for automotive project... not sure my friend wants everyone to know... Anyway, he blew few fuses because the project was taking too much current (must be over 20A)... This unit should be able to regulate that to whatever he needs...

As for the current rating, it's just the MOSFET used... you can go higher (or lower) if you change the mosfet (and the heatsink)... everything else remains the same...

Current controller can be used for all sort of things like variable DC motor speed, peltier cooling module, DC light dimmer, etc...

Cheers...