Announcement

Collapse
No announcement yet.

The Small Adjustable DC Voltage Digital 5A Power Supply Project

Collapse
X
Collapse
  •  

  • The Small Adjustable DC Voltage Digital 5A Power Supply Project

    By: Mark P.
    Parts Express Line Manager

    It’s inconvenient to lug a big, heavy adjustable 30V 5A DC power supply just to test a 12 VDC amplifier away from your bench. This kit helps shrink the weight and size by using an external AC/DC adapter that you may have laying around the house from an old laptop or portable DVD player. Parts Express Adjustable Step-Down Digital Regulator Board (#320-615) turns that old laptop adapter into a 3 to 19 VDC 4A variable power supply. If you want to increase the DC voltage range I recommend the Parts Express 36 VDC 5A AC Adapter (#120-063) and increase that voltage up to 32 VDC with up to 5A of current output.

    Why This See-Through Enclosure
    The Hammond 1591STBU (#320-725) is the perfect enclose for this project because its translucent blue poly-carbonate lets you see the blue back-lit digital display on the DC step down board without cutting a big rectangle hole. It’s only 7.5" x 4.3" x 2.2", but it has plenty of room to add any extra components to further customize this power supply project. You may add a lighted switch (#060-710), or a fuse holder (#070-612) to add extra protection, even though the step-down board has short circuit protection built-in. You will need to add a resistor if you use a power adapter greater than 12 VDC to prevent burning out the light in the switch.

    Putting the Project Together
    Now let’s build a small 3 to 32 VDC 5A digital power supply. Start by mounting the step-down the board to the lid using
    a standoff kit (#320-3290). Drill four 1/8" holes to match the board mounting holes. Secure four of the 16.25 mm standoffs to the lid using the Phillip screws included in the kit. Secure the board to the standoffs using the remaining 16.25 mm standoffs. Drill a 3/32" hole in the lid directly above each voltage adjustment push button. This enables a standard size test probe to adjust the voltage output up or down, plus adds ventilation to the board. Carefully drill a 7/16" hole in the rear of the box to mount DC power jack (#090-5018). Solder a positive wire to the center post and the negative wire to the long outer terminal. The other end of the wires will hook to + and - in. I recommend 20 or 18 gauge wire (#101-781) to handle the amperage. This power jack accepts 2.5 x 5.5 mm plugs, but if your AC adapter has a different size plug get a DC jack to match it. I chose this jack because the AC adapter (#120-063) I will be using has a 2.5 x 5.5 mm plug. Install the dual binding posts (#091-335) in the front of the box, by drilling two 1/2" holes spaced 3/4" apart on center. Take extra care drilling the larger holes to prevent cracking the ABS box. Use step drill bit set (#365-204), if needed, to gradually make the holes bigger. Solder or wrap the red and the black wire around the corresponding binding post or use crimp-on ring terminals (#095-674). The other end of the wire goes to the positive and negative out terminals on the board. Screw the lid to the box with the four included Phillip screws. Finally, plug in your AC adapter, and you have an adjustable power supply continuous from 3 to 32 VDC up to 5A.

    Small Adjustable DC Voltage Digital 5A Power Supply Project Part # 320-2900
    • Enables you to use existing AC adapters to save cost
    • Much smaller than desktop variable digital power supplies
    • It measures current draw of projects to determine which AC adapter is needed for permanent use

    Project Parts
    Part # Description Qty
    320-615 7A DC 60V Adjustable Step Down Regulator NC Power Supply Module Current Voltage Meter Buck Module 1
    320-725 Hammond 1591STBU Multipurpose Translucent Blue Poly-carbonate Enclosure 4.30" x 3.20" x 1.60" 1
    320-3290 PC Board M3 Standoff Kit with 8 pcs 16mm Stud / 8 pcs 10mm Stud / 4 pcs Phillips Screws 1
    090-5018 2.5mm Metal Panel Mount DC Jack 1
    091-335 Gold Dual Binding Post Banana Jack 1

      Posting comments is disabled.

    Categories

    Collapse

    Article Tags

    Collapse

    There are no tags yet.

    Latest Articles

    Collapse

    • Audioholics 2019 Product of the Year Award for best Budget Tower Speaker!
      by [email protected]
      Dayton Audio Challenges the Perception of Budget Tower Speakers

      DAYTON, OH (December 18, 2019) – The Dayton Audio MK442T Tower Speakers won the Audioholics 2019 Product of the Year Award for best Budget Tower Speaker!

      Building on the success of the MK442 center channel speaker, which was named Audioholics's 2018 budget bookshelf speaker of the year, Dayton Audio has since announced the release of the MK442T 2-way transmission line tower speaker.

      The MK442T...
      12-18-2019, 12:49 PM
    • Free Shipping Minimum Lowered - Parts Express
      by [email protected]
      Have you heard? Parts Express has lowered the FREE SHIPPING minimum to $49 for both Retail and Commercial Customers! (Previously $100 Retail, $500 Commercial)
      12-06-2019, 01:20 PM
    • Dayton Audio MK Boom - BOOM BOOM BOOM
      by administrator
      The Dayton Audio MK series of speakers have become a popular, fan favorite bookshelf speaker. Utilizing the same drivers as the great sounding MK series, the MKBoom DIY Bluetooth speaker kit carries on family legacy while adding grab-n-go portability.

      Powered by the efficient, yet robust Dayton Audio KAB-230v3 Bluetooth amplifier board, the MKBoom features 2 x 30 watts of output while minimizing power draw. Since power consumption is low, the amp board can be powered by 18650 Li-Ion...
      10-15-2019, 11:13 AM
    • 2019 Speaker Design Competition Winners
      by administrator
      The Midwest Audiofest Speaker Design Competition continues to shine as an exhibition of creativity, technical aptitude and audio excellence. Contestants traveled to our southwest Ohio location from as far away as New York, California, and South Carolina for this annual competition.

      Special thanks to our judges for contributing their ears and expertise: Jerry McNutt of Eminence, Vance Dickason, who founded Speaker Research Associates, and Tom Perazella, who is a Freelance Writer for...
      10-14-2019, 04:40 PM
    • B&C Speakers... Large Signal Parameters
      by administrator
      Written by: Bennett Prescott

      Every loudspeaker designer should be familiar with Thiele/Small parameters1, usually abbreviated T/S. Originally defined in the 1960s, they are a simple model of how transducers behave – mostly useful for designing ported cabinets like subwoofers. In 1971 they were brought to the attention of the US audio world by A. Neville Thiele, a native Australian, and Richard H. Small, a San Diego native who moved “down
      under” to work with Thiele. This...
      10-14-2019, 04:28 PM
    • HOW SPEAKERS ARE BUILT: A Look Inside the Eminence Factory
      by administrator
      By Cobi Stein

      The first electronic loudspeaker designs were introduced in the 1920s, and while there have been many improvements in component materials over the decades, not much has changed in the basic functionality of a loudspeaker: a permanent magnet interacts with an electromagnet (voice coil) to move a cone back and forth, which produces sound waves. Founded in 1966, Eminence has been a leading
      supplier of loudspeakers for professional audio, musical instrument, car audio,...
      10-14-2019, 04:08 PM
    Working...
    X