IRLZ34N in JL 1000/1

[shagone]

i need to replace a IRLZ34N in JL 1000/1 that is shorted. it is not on the sync but near the middle of the board.

is this part of the regulated voltage circuit? what is a good substitute for this part? irfz44n? irf540n? i have both of those available.

the big green bodied resistor near this fet is burned looking to.

[Perry Babin]

If this is the FET near the yellow transformer near the center of the board, yes. It's the power supply for the low voltage circuits.

The L in the part number means that it's a logic level FET and is designed to turn on at a lower gate drive voltage than the Z44 or the 540. They will probably work (Z44 suggested) but they may run hot if the drive IC doesn't have enough drive voltage.

The transformer may be shorted or there may be a shorted component on the secondary side. If you can get to the resistors between the filter caps, you can measure the voltage across them to determine if there is excessive current draw. If there's excessive current draw, one is likely to show signs of overheating.

You also need to confirm that you have a good square wave drive on the gate of the FET. If it's DC or doesn't go to ground, the drive circuit may be damaged.