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I'm attempting to drive an array of piezo transducers and am struggling to find a good design capable of driving from around +-5V to +-30V at about 2A for my testing. There are about 12 sets of transducers that will need to operate independently and thus require their own driving circuitry. I am planning to use half H-bridges for this. Something like this image:

enter image description here

I've got access to a 0-30V, 10A supply, but most of the circuits I've come across for split rail designs are a bit underpowered and intended for fixed voltages such as this one:

Virtual ground circuit

I also looked at using something like an LM1370 (500kHz High Efficiency 6A Switching Regulator), but it seems as though it may underpowered too.

I apologise if this question is a bit open-ended, but if anyone has any advice on an reasonable solution for this, I'd be very grateful.

Thanks in advance for any help!

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    \$\begingroup\$ Why do you need a dual-voltage supply when you're using H-bridges? H-bridges generally use a positive supply only and generate AC by alternately switching the devices terminals to V+ and 0 V. \$\endgroup\$
    – Transistor
    Commented May 13, 2016 at 15:47
  • \$\begingroup\$ I was planning to use a half H-bridge design which uses the dual rails, to save on component numbers if I implement a full H-bridge. I added an image to clarify. \$\endgroup\$
    – Cotlone
    Commented May 13, 2016 at 16:17
  • \$\begingroup\$ That sound like a lot of current. You could look into various smps/ DC-DC converters. Or maybe just buy another 0-30 V power supply. \$\endgroup\$
    – George Herold
    Commented May 13, 2016 at 16:26
  • \$\begingroup\$ Yes, I'll be looking at various transducers designs for this research. There will around 120 transducers, so I am just over engineering the supply to give me more flexibility. I did consider getting another 0-30V supply. \$\endgroup\$
    – Cotlone
    Commented May 13, 2016 at 16:46
  • \$\begingroup\$ Just another idea to think about. Use a half-bridge, set to fixed 50% duty cycle, put a LC filter on the output. It is basically a synchronous buck. Obviously, the half-bridge output components have to be sized to your power and ripple requirements. \$\endgroup\$
    – rioraxe
    Commented May 14, 2016 at 0:29

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I'm attempting to drive an array of piezo transducers and am struggling to find a good design capable of driving from around +-5V to +-30V at about 2A for my testing.

Piezo's are capacitive and don't care if there is DC content across their terminals or not. Just design a single-sided H bridge and if you are really worried then use a capacitor in series with your piezo, just like a push pull audio amp does with a ground referenced speaker and a single-sided supply: -

enter image description here

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  • \$\begingroup\$ I'm not sure the "flavor" of the OP's piezo, but I use some that are DC devices. (position control) \$\endgroup\$
    – George Herold
    Commented May 13, 2016 at 16:29
  • \$\begingroup\$ @GeorgeHerold do you have a link - it would be useful to me. \$\endgroup\$
    – Andy aka
    Commented May 13, 2016 at 16:32
  • \$\begingroup\$ Thanks for the replies gentlemen. Due to my application, I'm interested in the dilatation part of the waveform, which is why I was considering split rail. I'll look further into using a push-pull design with the series capacitor. \$\endgroup\$
    – Cotlone
    Commented May 13, 2016 at 16:56
  • \$\begingroup\$ @Andyaka thorlabs.de/newgrouppage9.cfm?objectgroup_id=8040 thorlabs.de/newgrouppage9.cfm?objectgroup_id=61 Well here are a few, we use something like the second link, but buy from a distributor (not Thor labs.) These are ~100V and move a few microns. I can look up the part number and distributor if that is what you might be looking for, \$\endgroup\$
    – George Herold
    Commented May 13, 2016 at 17:33
  • \$\begingroup\$ @Cotlone, I should add that these piezo actuators are polarized... they do not like too big a reverse voltage. \$\endgroup\$
    – George Herold
    Commented May 13, 2016 at 17:35

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