Need Help Can`t determine what this chip is

Thread Starter


Joined Oct 15, 2008
I have a circuit board that is a brushless motor speed control. It is now dead, no control at all.
It has two rows of 8 - 8pin surface mounted I.C
The first have the following printed on them: I R P026H U2E4 F9310 ----(In the PO26H, could be O or 0, not sure)
The second row: I R P126H BOU3 F8788

What kind of MOSFETS are they? I tried to google search and could find nothing. If they are NOT expensive, I would like to try to replace to see if I can get it to work again. If possible, maybe one step in higher specs, again if NOT costly.

Please let me know what you think.
No I can`t get any help from the maker, besides buy a new one. I think heat did the damage, when you see the maker had NOT used heat sink compound to aid in heat transfer to the aluminum heat sink BUT a form of tape.
Thanks for your Time and Help.
First Row MOSFETS are IRF9310 (P channel MOsfets) and second row mosfets are IRF8788 (N channel). P channel mosfets are high side mosfets and N channel mosfets are for low side mosfets in Driving circuit.

May be surge damaged the IC. They didnt use the heatsink because application ratings(Voltage , current ) are less for reaching maximum junction temperatures of MOSFET IC ( may be below 70 to 80 C).



Joined Jul 13, 2015
Did you tester the resistance of each mosfet out of the circuit. If this good ,look the driving circuit.,
that drives the mosfets. As you guess ,you said i think..... you did not tell if you done removing it.