Mosfet Help

[atz88]

Hey all,

Need some help in working out what is goin on with my mosfet.

Mosfet : IRFB38N20DPBF
200v 44amp N- Channel

Its use: It receives a pulse from the output of my 555 (12-13v) an allows current to flow from the - terminal of a transformer to earth. (also 12-13v)

Problem: Im not getting any pulsing on the Drain Source side.

Troubleshooting: I have hooked it up to battery with the gate through a 50k resistor an without, and with a lamp as the load but stil get the same result which is. The drain- source stays on an eventually fades off, then when i turn the gate on, it does the same, the pulse of the on time is about 1min, where as i need it to be 400hz....

Any help would be greatly appreciated

[sauravgoswami]

Check the pulses of 555,and you can set the pulse @400Hz from 555,change the MOSFET and see if the problem still persist.

[atz88]

yep checked the pulse from the 555 to gate at 400hz, an its a new mosfet
how would you set it up in relation to resistors etc, im new to transistors sorry ?

[just2rock]

if you have a Mosfet : IRFB38N20DPBF TEST jag then first check the respective MOS for any errors etc.and then later for application onto PLC board.Its 555 application can be monitored with Astable/Bistable /Monostable operations.

[sauravgoswami]

Why dont ya replace the mosfet with some other equivalent Mosfet