How much current does this Opto isolator output (HCPL-3180)?
How much current does this Opto isolator output (HCPL-3180) ?


The first page of the data sheet gives some strong clues that I have enhanced with red boxes: -




  I wanted to know the average current which will be fed to the MOSFET


If the MOSFET gate-source capacitance is (say) 10 nF and it gets charged to (say) 12 volts, then the peak current will be as stated above (2 to 2.5 amps) and the charge time will be decided by this formula: -

$$i = C\cdot \dfrac{dv}{dt}$$

Plugging in 12 volts for "dv" and 2 amps for "i" gives a "dt" (time) of 60 ns. This will be an approximate value because the current will be falling from 2 amps to zero amps over the charge period but something like 100 ns will be reasonable.

If you are switching the MOSFET at 1 MHz, you can make a reasonable argument that 1 amp flows for 100 ns and zero amps flows for about 900 ns repeating every 1000 ns. This approximates the average current to 100 mA.