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Which H-Bridge driver can I use for power supply amplification?

  1. Mar 5, 2012 #1
    I have been tying to design and build a dc to ac inverter. I want to convert 10v dc to 25v ac @ 50hz. I want to use a pic24h microcontroller to generate pwm waveforms to control a H bride driver. I have programmed the pic24h to produce pwm waveforms. I used the LMD18200 as the h bridge driver only to find out it is only to be used for dc motor applications. I want a pwm waveform that goes postive and negative at the output of the h-bridge so that i can filter it(to get a 50 hz sine wave). Can anyone please suggest a H- bridge driver for me or refer me to its datasheet?

    Thank you in advance.

    Alex Arthur
  2. jcsd
  3. Mar 5, 2012 #2
    i dont know, but i think your idea is missing a step. i doubt your going to get a driver which will drive below the power rails. you could use an isolated transformer on the output, or a switch-mode generated negative rail, then any H-bridge arrangement should work.

    is it for powering something? what is the goal here? how about using an audio class-D power amp IC.
  4. Mar 6, 2012 #3
    The driver is not going to get its power supply from the micro controller, its only getting its input logic from the micro controller. Its not powering anything, I just want to see the 25v ac on an oscilloscope. So I''ll just put a resistor as the load. It is supposed to simulate a solar panel being tied to the grid. However I can't work at high voltages
  5. Mar 6, 2012 #4
    Sorry! the H-bridge will drive a transformer which will be tied to the grid.
  6. Mar 6, 2012 #5
    Hi ...
    I have not seen any H-bridge producing a pwm output switching between positive and negative voltages ... But u can feed that pwm signal to a LEVEL SHIFTER or CLAMPER circuit to shift its DC LEVEL appropriately to get both positive as well negative-going pulses , right ???
    Then , u can filter that waveform to get sine wave , right ???
  7. Mar 6, 2012 #6

    jim hardy

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    That H bridge has two outputs that are tied alternately to Vsupply and common

    So, will voltage between output 1 and output 2 not alternate between + Vsupply and -Vsupply ?
    Would a voltmeter connected there not report that?
    A transformer winding connected there would see AC voltage.

    Remember voltage is potential difference
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