Author Topic: driver ic  (Read 1314 times)

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driver ic
« on: July 13, 2014, 14:14:29 pm »
i was looking into mosfet drivers and i just meet this ir2121  called current limiting gate driver

seems pretty cool...


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some fix
« Reply #2 on: July 14, 2014, 08:54:28 am »
doesn't it seem cool...

I think with this on the saturation current can be set and if you vary the frequency it aways send the max voltage it can to keep the curet at max.....

I use a simple 4427 just to send the signal to the mosfets... i did this comment just to tell you that i found that my mosfet driver was not working properly and my transistors were burning mainly because of this.. basically the driver was still kind of working but the waveform at higher frequency was rounded not a decent square... , hopefully it were a dual chip driver so i took the other exit and connected thru two anti paralleled 1n4148 diodes to the gate... with no resistor this time...

all this because i had a test point in the circuit just after the pll so the waveform aways looked good in the oscilloscope, i was just taking the signal before the point of interest.

I now connected my variac to the 240v line too (because this is its voltage)  so it can puts out up to 2a up to 250v so 500VA

Good idea is that i made some servicing in the variac, i made thinner the tip point of the graphite of the wiper arm in the variac and i realized how lazy we are in terms of how to do a variable coil...


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Re: driver ic
« Reply #3 on: July 14, 2014, 17:54:11 pm »
Yea i think this would work well for helping prevent saturation of the transformer..   especially since we are not desiging a transformer to operate under set parameters.. such as the fact we are varying the frequency in most cases and we can encounter saturation accidentally much easier due to that.. which can lead to component failure in some cases

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Re: driver ic
« Reply #4 on: July 14, 2014, 18:00:24 pm »
Yes i agree... I think this may be accomplished in stan design by the voltage attenuation system but here is should be kind of automatic...  don't you think?

I guess thats were its all about...

The pulse should get modulated... being reduced in width to keep the core from saturation..

« Last Edit: July 15, 2014, 00:17:54 am by sebosfato »