Miniaturized AC/DC converter high amps

Discussion in 'The Projects Forum' started by jjmalove, Jul 21, 2016.

  1. jjmalove

    Thread Starter Member

    Jul 6, 2016
    One aspect of a project I am working on that is in the prototype phase involves taking 110V or 220V AC (depending on install location) and converting it to a 9V DC output to power some PCBs. Our current solution is a COTS AC/DC converter, which works fine for the initial development and prototyping. We have a second project that involves a COTS DC/DC converter with a Deep Cycle Battery to keep a steady 12V output with high amps regardless of the charge % of the battery.

    For the future effort, I want to design my own AC/DC converter using the most miniaturized components available to get the same output and amps in a small package size. Likewise I want to design my own DC/DC converter with similar goals.

    Can anyone point me in a good direction towards resources to accomplish this? The main goal is taking a schematic of some decent converters and redoing them using more expensive, smaller parts and a custom PCB. I know that off the shelf converters don't use the most expensive stuff and are not as miniaturized as possible due to keeping cost down, but for our projects cost is not that important. At first glance I'm thinking swapping out the big through hole parts for as small of SMD resistors and ceramic caps I can get away with regarding watt and voltage maxs, and then QFN style ICs instead of DIPs and such. Perhaps a 6 layer board as opposed to 2 or 4 layer that the COTS converters are to squeeze things closer together. Also removing all quality of life peripherals like connectors, buttons, leds ect. and making it as bare bones as possible with simple soldered wires to pads.

    Thanks in advance!
  2. AlbertHall

    AAC Fanatic!

    Jun 4, 2014
    How many amps?
    How many volts?
    Is this going to be part of a commercial product (and hence needs to meet EMC requirements)?
    Are you experienced designing PCBs for switch-mode power supplies?
  3. jjmalove

    Thread Starter Member

    Jul 6, 2016

    For AC/DC Converter it would always be input 110V or 220V depending on location, with some sort of toggle switch similar to computer power supplies for instance. Output would always be 9V DC. Amps requirement is an interesting answer currently. So for our demo/prototype its minor, 3A max so a COTS solution is working just fine. The end product wants to be modular, as in a customer may want 10 devices tied together or 100. So I'm hoping for some sort of modular power supply as well that say, each one powers 5 devices, and if they want 6-10 we use 2 power supplies, 46-50 we use 10 power supplies ect.

    For DC/DC Converter it would always be input of a 12V Deep Cycle Battery, so those have a swing of about 10-14.5V. Output would always be 12V DC. That design won't be modular like the other one, but the amp load will be 15A max at 12V DC.

    Both are military products, so will be in final form mil-spec standards. I'm more just throwing around some ideas at the moment, we haven't finalized anything for sure. Some details have to be off the table due to the nature of the work, but the important part is that the first one is powering a bunch of various PCBs from an AC wall source, and the second is powering only a few PCBS but they are power hungry and its from a deep cycle battery. The second one has its own separate heat issues as well and will involved some active cooling but that is being handled by someone else currently.

    I'm not very experienced in design, but will also have more experienced people to get help from as well. Very knowledgeable about electronics just newer at the engineering side of it (been a technician for many years).

    I was mostly hoping if there was a nice website with lots of converter designs I could browse through and get some ideas? I know the basic concept of how they were but I find I do well dissecting working designs to learn how they work and make my own better than starting from scratch.