I wanted to use it like this in this configuration][How much current does this Opto isolator output (HCPL-3180) ?
1 Answer
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.
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\$\begingroup\$ thats the peak current , I wanted to know the average current which will be fed to the MOSFET \$\endgroup\$ Commented Dec 27, 2018 at 12:45
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\$\begingroup\$ I have uploaded a picture of what Im trying to achieve, I wanted to know the average current which outputs by the driver so i can calculate the value of the charging and discharging resistors, using the formula Qg = Ig* t , or if i could find out the time \$\endgroup\$ Commented Dec 27, 2018 at 12:53
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\$\begingroup\$ My amended answer should give you all the information you need. If you want a more precise answer, use a simulation tool. There are quite a few free ones available. I use micro-cap. \$\endgroup\$– Andy akaCommented Dec 27, 2018 at 12:59
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\$\begingroup\$ so if my VGS is 15V and the total input capacitance of the MOSFET is 19860pF and I am generating PWM from an Arduino with a frequency of 4kHZ how do i go about it, sorry I am student \$\endgroup\$ Commented Dec 27, 2018 at 13:10
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1\$\begingroup\$ @DanielBashy please DO NOT evolve this current question the way you have by adding that new circuit diagram. Ask a proper new question for this different subject else it makes my answer look stupid and incomplete. \$\endgroup\$– Andy akaCommented Dec 27, 2018 at 13:55