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What is the most efficient / best way to make an H-bridge? I want low power loss but also fast switching time since I will using PWM. I have considered using 2 P-channel and 2 N-channel MOSFETs to make this. But, I realized that P-channel devices have a much higher channel resistance causing more power loss.

So, I was considering using 4 N-channel MOSFETs but the problem lies with the gate voltage. My power source will be approximately 15V and I am going to be using a arduino/atmega for PWM signal (5V). So, I am wondering what is the best way to amplify this gate voltage so that the high side N-channel MOSFETs turn on while also giving me a rapid switch time. Or, am I digging a hole for myself and should just stick with a P-channel?

Phil Frost
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  • possible duplicate of driving low side of a mosfet bridge with 3.3V – Phil Frost Aug 06 '13 at 13:58
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    There are really at least three problems here, each complex enough to merit separate questions: 1) driving MOSFETs in parallel, 2) using N-channel MOSFETs for the high side, and 3) designing a proper gate driver to switch MOSFETs quickly. If the general answers already here don't address your question, I'd suggest you edit or ask a new one to be more specific. – Phil Frost Aug 06 '13 at 14:06
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    How much current? What sort of switching speeds are you talking about? Have you considered an integrated solution (IC)? – Tut Aug 06 '13 at 14:19
  • What do you mean by low power loss? 2) When saying that you'll drive it by PWM, do you mean that you'll employ LPF to integrate the PWM, or each high phase of PWM should open the MOSFETs?
    • – Vasiliy Aug 06 '13 at 14:35
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    I'm not being sarcastic, it seems from your wording you don't know these exist. Gate Driver IC's – Matt Aug 06 '13 at 14:51
  • Take a look at OSMC (Open Source Motor Controller) website, that will give example circuits (at least for motor control) but you need to give more info for a more exact answer, ref previous comments. – Jay M Aug 06 '13 at 20:40
  • See my answer to http://electronics.stackexchange.com/questions/78943/how-can-i-switch-a-high-side-transistor-from-logic-referenced-to-ground/78979#78979 – Szymon Bęczkowski Aug 15 '13 at 15:36
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    @Matt Anderson I think if you are not being sarcastic you are at least not helping so much. Gate driver ICs are not a standart, and have many pros and cons, as having so much types of implementation too. For a infinity on-time of the high-side switch, a boot-strap gate drive IC, will not work (only if using a isolated supply for the high side, so no bootstrap will be used). – Diego C Nascimento Sep 11 '13 at 10:02