Benchtop Power Supply

thingiverse

To be honest, if you want a benchtop power supply for your hobby electronics projects and you're looking around on Thingiverse I'd recommend you just go and buy a commercial PSU; done and RTG. You don't build one from scratch because you're going to save money, or get a better final product. A commercial benchtop CV/CC PSU has already been optimized for both cost and performance; clearly the more you spend generally the better the final product will be. Having said that, if you have a large-ish 3D printer, some spare parts sitting around, plenty of filament, know how to safely terminate wires containing line voltages, and time on your hands...and understand the DIY route with all it's pros and cons, then maybe this design, in all it's half-sorted glory, is interesting. Disclaimer ============= Look, any type of DIY project that involves wiring of line circuits (i.e. circuits that you plug into the wall socket) are best left to the pros if you are not intimately familiar with safety and building codes in your local region. In some places around the world, this type of home-made device may well be illegal. I uploaded this info for entertainment purposes only, I am not a professional. If you decide to build this, you take 100% ownership and liability for this decision and the consequences that may follow. And if you've made it this far, you should be rewarded with some details. Description ========= Heart of this benchtop PSU is the excellent [RDtech DPS3005](https://www.aliexpress.com/item/1000004279003.html) A 36Vdc 360W SMPS provides power to the DPS3005. Additionally it feeds three LM2596 dcdc modules set at 12Vdc, 5Vdc and 5Vdc. These voltage rails are routed to a series of standard banana jacks (gold plated copper speaker terminal binding posts). There's a dual USB type A socket (on a dedicated LM2596) so you can charge your phone, bluetooth speaker or that batch of 18650 batteries you have laying around, or confirm your hobby project will work on USB power directly. The internal 36V power supply has a fan to keep it cool, and the hot air is ported thru a shroud directly to the outside. Makeup air is drawn from the back to cool the power supply, and top cover to cool the DPS3005. If the fan is not running, the DPS3005 is cooled passively (haven't pushed it hard, don't know if that's enough). On the top cover are plenty of pockets to hold the resistors, caps tools and other bits you'll need for your hobby project. Parts you'll need ============= >RDtech DPS3005 dcdc converter. $30. https://www.aliexpress.com/item/1000004279003.html >36Vdc switch mode power supply. I used "S-360-36". Takes 110/22Vac input and produces 32Vdc 10A output. approx $30. Check on AliExpress, Ebay or Amazon. >4 of flat head screws for the SMPS, iirc they were M3 x 15mm >3 of LM2596 adjustable output DCDC modules. These can be had on ebay for <$2ea. >IEC320 C14 power inlet module, with integrated switch and fuse. Can get these on ebay for ~ $3 ea. >4 of "speaker terminal binding post banana jack". 3.5mm ID, 19.05mm spacing. >A dual thru hole USB typeA socket. [Example](https://www.digikey.com/en/products/detail/adam-tech/USB-A-D-VT/9832305) >A handful of small woodscrews. Drill and bits to match. >Wirenuts (marretts) or Wago connectors >Female blade terminals, Ferrules, associated crimping tools, heat shrink >14ga or larger stranded wire, rated to handle AC line power. >Hot Glue gun & glue >Soldering iron & soldering accessories >~600g of filament >a 3D printer with a minimum bed dimension of 276mm >...and lots of time Assembly ======== If you've decided to build this, it's likely you don't need assembly instructions. But a couple design intent bullets might help. * LM2596 modules are intended to be hot-glued to the _dcdc frame_ * _dcdc frame_ is intended to snap fit and be glued to the _base_ * all LM2596 modules are connected directly to the 36Vdc output of the SMPS. Don't forget to set the output voltage of the LM2596 before you glue the assembly into the _base_. * _fan shroud_ is intended to be snap fit and glued to the _base_ * USB socket is powered from a dedicated LM2596 set at 5.0Vdc output. * 5V banana jack is powered from the other LM2596 set at 5.0Vdc output (not shared with USB power). Best of luck!