[SOLVED] ir2110 drive boost converter short circuit

[mshh]

i used ir2110 to drive boost converter (low side switching) but when i connect the source input it make short circuit and the dc source turned off. i don' know the reason i simulate it on Proteus and it works fine.
note; i didn't find ir2110 in proteus so i used ir2112( they are the same )

 

[KlausST]

Hi,

The IC has undervoltage lockout on both channels.
So don't be surprised when it shuts down when you don't power high side driver.

And you violate V_IH level.

Klaus

 

[mshh]

i didn't get you where is the problem? i used the low side so Hin is connected gnd

 

[FvM]

Yes, low- and high side driver are working independently. High side UVLO doesn't affect low side.

The problem report isn't very clear. Are you talking about shorted power transistor, defective IR2110?

 

[mshh]

short circuit happened on the input terminal of the dc converter, when i removed the input terminal and measured voltage using voltmeter i found 6.5 v on input?!!

 

[KlausST]

Hi,

Indeed I can't find a clear information whether both UVLO work independently or not.
From the drawing I see no connection. So maybe FvM is right.

Still you violate V_IH.
But this does not explain short circuit.
I assume the schematic does not match the test circuit.

Klaus

 

[Akanimo]

It seems like the inductor is saturating. If the inductor is saturating, it would draw a lot of current from the supply. If the supply has a current limit setting and protection, then it would turn off. I doubt Proteus does simulate core saturation. Some simulators like LTspice does.

Try it with low PWM duty cycle to see if it would still shut down.

--- Updated Nov 25, 2020 ---

What's the input voltage of your converter?

 

[mshh]

The input voltage is 12v from pc power supply. But why would the inductor saturate? ,there is no load yet. And the transistor is good

 

[KlausST]

Hi

I think Akanimo is correct.
It's not a true short circuit, but just high current.

See the current flow path when the Mosfet is ON. --> Load is not involved
And after some 10us ... or some 100us the current will become high, too high. The inductor will saturate, thus the current will rise even faster.

Klaus

 

[mshh]

yes that's right, it's the normal operation of boost converter to draw current even without load being connected. the current was high because it wasn't controlled.
thanks