EEVblog Electronics Community Forum
Electronics => Projects, Designs, and Technical Stuff => Topic started by: Deadpixel732 on August 24, 2013, 10:09:40 pm
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Hey guys,
I have a question.
If I wanted to drive a 4 N-Channel H bridge with a UCC27525 (Dual 5-A High-Speed Low-Side Gate Driver), could i do it (supplying 12v to vdd of chip) even though the chip is classified as a "low side gate driver". 12V is within the power limitations of the UCC27525 and would be enough voltage to successfully switch my mosfets (CSD16342Q5A) highside with a 5v load so it seems like it should work. My guess is that its classified as a low side driver because of the relatively low vdd voltage limit compared to other high side drivers that can handle 100v+. Or maybe there is some other huge difference im missing.
UCC27525 datasheet: http://www.ti.com/lit/ds/symlink/ucc27524.pdf (http://www.ti.com/lit/ds/symlink/ucc27524.pdf)
CSD16342Q5A datasheet: http://www.ti.com/lit/ds/symlink/csd16342q5a.pdf (http://www.ti.com/lit/ds/symlink/csd16342q5a.pdf)
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It's a low side driver because it drives the gate to ground to turn the MOSFET off, a high side driver drives Vgs to 0 ... if your power supply for the bridge was >8 Volt you would be exceeding min Vgs when turning off the high side MOSFET.
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well the gate should be able to handle +/-20 vgs so it would work,
why you would bother i don't know, a five volt load means you've got hundreds of high and low side drivers, many that can handle 5 amps of gate drive just fine.
what are you driving that needs 5 amps of gate current?
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Or maybe there is some other huge difference im missing.
yes, high side drivers are floating and most of them are powered by a bootstrap capacitor and a diode, they also have a level shift network involving pulse generators... take a look at the datasheet.
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well the gate should be able to handle +/-20 vgs so it would work,
why you would bother i don't know, a five volt load means you've got hundreds of high and low side drivers, many that can handle 5 amps of gate drive just fine.
what are you driving that needs 5 amps of gate current?
Well actually I just need any mosfets driver that can drive the mosfets ive linked highside (with 5v load), be able to switch at around 750kHz to 1Mhz, and have one of its outputs inverted.
I anyone could, I would really appreciate a few recommendations.
Thanks.