IR2110 Mosfet/IGBT Gate Driver - Three phase inverter for BLDC motor - help needed

Thread Starter


Joined Jan 31, 2013

my project: speed control of BLDC motor (square wave BLDC)...

my motor(load) specifications are: 24VDC(for inverter) 0.25HP 3000RPM and by calculations it shows current rating will be 8Amp
so the inverter should be designed for this specifications...

with the help of datasheet i designed the mosfet gate driver circuit, i have attached my circuit diagram here...

i have soldered this circuit in board....

for gate pulses, i used arm processor, 120 deg mode, given in correct sequence...

when i checked this circuit with just resistance load 1k ohm, the inverter output was step wave, only 10V peak to peak,
whatever input given to inverter, i got only 10V not exceeding it..

when i connected motor to this circuit, motor started at very less speed, and after few seconds, mosfet got burnt..

i checked this forum for the circuit, i found many corrections in my circuit....

so, i attached what i did in my circuit

friends, please guide me in solving my problem...



Joined Jul 9, 2011
Connecting the sources is an absolute MUST.

Do you have an oscilloscope?

Post pictures of your layout and the signals measured with the scope.
Okay so there are a few basic mistakes in the circuit. I know the post is old but it may help anyone searching over internet with similar issues. There must be a 10k-20k ohms gate-to-source resistor ( Generally known as Pull down resistor ). You should use a gate gate resistor of around 20 ohms. Moreover, the IR2112 is based on bootstrap topology which has many technical complications, you may switch to isolated dcdc based gate driver topology to make it simple for you. I had a similar project and i switched to isolated gate driver topology. I used a gate driver module of cree CGD15FB45P1 but it was really expensive. later i switched to GDA-2A6S1 which had short circuit protection and was less expensive. Hope that helps.