I have a very simple MOSFET switch I'm using to turn on an emergency night light. The circuit works OK - very simple after all - but the MOSFETS heat up way more than I expected.
The MOSFETS are IRFP4310ZPb - and I use TWO of them in parallel to drive a little 50W, 12VDC lamp. Each of the MOSFETS is rated at 134A, so I was expecting these two not be barely warm. Besides, the light isn't even on 100% - it's run at about a 50% duty cycle (blinks).
Instead, the things are up to about 135 degrees (each has a little heat sink - I'm using ones designed for a TO220 package, not the TO247 of the actual fets, but the cooling of these is rated almost the same. Using thermal grease).
This is a simple circuit - apply 11VDC to the gate, 12VDc source, 50W load.
Isn't this WAY too much heat for this 50W load???
(thx in advance)
The MOSFETS are IRFP4310ZPb - and I use TWO of them in parallel to drive a little 50W, 12VDC lamp. Each of the MOSFETS is rated at 134A, so I was expecting these two not be barely warm. Besides, the light isn't even on 100% - it's run at about a 50% duty cycle (blinks).
Instead, the things are up to about 135 degrees (each has a little heat sink - I'm using ones designed for a TO220 package, not the TO247 of the actual fets, but the cooling of these is rated almost the same. Using thermal grease).
This is a simple circuit - apply 11VDC to the gate, 12VDc source, 50W load.
Isn't this WAY too much heat for this 50W load???
(thx in advance)