What is the input current limit of IR2110????

[biswaIITH]

Hello everyone...i am using TLP350 to drive IR2110 (i.e. Hin and Lin) with out any current limiting resistor...i.e. arduino---->TLP350.....>IR2110......>Mosfet...But each time i m applying the voltage to the circuit..The TLP 350 and IR2110 gets heated up..Is it because of the absence of any resistance between TLP350 and IR 2110...As the output current rating of TLP 350 is 2.5 Amp

 

[amayilsamy]

Hi...

Refer this link..

https://tahmidmc.blogspot.in/2013/01/using-high-low-side-driver-ir2110-with.html

 

[biswaIITH]

Ya sir..i am already following the circuit given in the above link...but i am directly giving pulses to TLP 350 from my arduino...From TLP 350 i am giving pulses to IR2110 (Hin n Lin) with out current limiting resistor...The current rating given in the datasheet is 40uamp and 1 ump respectively for two logic inputs....I guess output current of TLP 350 is exceeding the limits

 

[amayilsamy]

IR2110 works with logic supply 5V, So don't need TL350 and no need resistor.

Read the datasheet page # 3

 

[FvM]

Input current specifications of logic inputs have nothing to do with "current rating". They are an information about expectable current of this high impedance inputs. There's no risk of overloading the inputs as long the input voltage is in the permitted range, in this case if TLP350 and IR2110 share the same power supply.

TLP350 can overheat if the LED input current isn't properly limited or if the switching frequency is too high. And of course if the supply voltage limits are exceeded.

I also don't understand why you are using TLP350 with IR2110. TLP350 has sufficient gate drive capability, it won't be increased by adding an IR2110. You would rather use a fast logic level optocoupler in front of IR2110 or TLP350 stand alone.

 

[biswaIITH]

Input current specifications of logic inputs have nothing to do with "current rating". They are an information about expectable current of this high impedance inputs. There's no risk of overloading the inputs as long the input voltage is in the permitted range, in this case if TLP350 and IR2110 share the same power supply.

TLP350 can overheat if the LED input current isn't properly limited or if the switching frequency is too high. And of course if the supply voltage limits are exceeded.

I also don't understand why you are using TLP350 with IR2110. TLP350 has sufficient gate drive capability, it won't be increased by adding an IR2110. You would rather use a fast logic level optocoupler in front of IR2110 or TLP350 stand alone.

Actually one of my juniors is using the above architecture...i also advised d same i.e. there is no point of using both TLP 350 and IR2110 together...As it is too late to chng the circuit,he is continuing with the same...But the question remains why the IR2110 and TLP350 are getting heated up....

 

[FvM]

It didn't say it can't work, just said it's useless.

I also answered the question about possible reasons for heating. Heating of both devices suggests (too?) high switching frequency. For a detailed discussion, we should see the exact circuit schematic and receive some more information about the application.