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I'm building a switching power supply taking 12V to 19V at 3A max out. I've already built one of these using a Schottky diode for the rectifier, but this time I'm thinking of trying a high-side-switched N-channel as the rectifier to reduce losses. The end result is to power a small computer based on a battery input (range 9.9V -> 16.8V, 3S or 4S LiPo.)

The battery circuit is separately fused/switched; this is the boost power supply part only.

My question is: The MOSFET driver IR2183 has a "typical circuit" that ties the VS signal for the bootstrap capacitor to the load in a different way than I'm doing here. Specifically, it shows the load as connected between the source and drain of the two MOSFETs, whereas I tie them together to provide a single output. Will the 2183 still properly bootstrap the gate drive of Q4? My guess is "yes" but I'd like a double-check by someone who's ideally done this before :-)

MC34063 and IR2183 based boost converter

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    \$\begingroup\$ Looks fine to me. \$\endgroup\$ – Dave Tweed Apr 27 '13 at 20:35
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Here's the checklist

  • IR2183 has a bootstrap mechanism.
  • IR2183 has built-in circuit for shoot-through prevention. (If it didn't have a built-in one, you would have to add an external one.)
  • IR2183 can operating at frequency up to 400kHz. Operating frequency of MC34063 is 100kHz. In the circuit, MC34063 is set to operate at roughly 50kHz.

So, yes, it should work.

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It may work, but badly.

IR2183 has built-in circuit for shoot-through prevention - true, but it lacks zero-cross detection. So especially after you had a short L1-charging pulse via Q3, the stored energy quickly is transferred via open Q4 to the C4 and c5 and then backwards - via the still open Q4 -> L1 -> +15V (low side Vcc)

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