A Superpower Supply
Many of you have built your own power supplies. Here is a buy and assemble kit, given as a PCB file, a parts list and a schematic, to serve as a starting point or final hardware for either a dual positive supply or a positive and negative supply. It's configured with the regulators at the card edge to allow them to be easily attached to heat sink(s).
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The PCB, supplied as an ExpressPCB file, can fit either a Triad or Amveco toroid. The regulator connections are for LM78xx and LM79xx for positive and negative output, so you can use this with two SPX78s or one SPX78 and one SPX79. Or you can go cheap and use standard monolithic devices. Either transformer can be wired with secondaries in series to increase (double) Vrms, note that this limits the circuit to a single output.
The two circuits have isolated ground reference connections that can be tied together at the load to prevent ground current cross–talk between the two power supplies.
Positive+Negative Superpower Supply Schematic
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Dual Positive Superpower Supply Schematic
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Positive + Negative PCB
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Dual Positive or Positive/Negative Supply
We offer two different PCBs, one with dual positive supplies and one with positive and negative supplies. Both use dual primary/dual secondary toroidal transformers. The dual primary allows 120V input (inputs in parallel) or 240V input (inputs in series). The PCBs are 2.5x3.8 inches each.
Dual secondaries can be connected in series for higher voltage or in parallel for higher current. If the secondaries are placed in series, only a single supply can be built. Two transformers are in the parts list, the Triad can be used for dual outputs at 2A each, with regulated Vout between 3.3V and 7V (positive or negative depending on your selection). At 3.3V out, the regulator(s) will dissipate 10W at 2A and thus the need for the heat sink you see in the photo.
Parts List
All parts except PCB, heat sink and Amveco transformer are available at http://www.mouser.com/, Amveco transformer available at http://www.digikey.com/, PCB and heat sink available from the links given.
| Qty | Ref. Des. | Value |
Description | Part Number |
| 1 | Positive+ Negative PCB from OSH Park | see text | Download Gerber/Excellon files (zipped) to order positive+negative PCB | After you download the zipped file, go to http://www.oshpark.com/ and submit it, you get 3 boards for about $48(US). |
| 1 | Dual Positive PCB from OSH Park | see text | Download Gerber/Excellon files (zipped) to order dual positive PCB | After you download the zipped file, go to http://www.oshpark.com/ and submit it, you get 3 boards for about $48(US). |
| 1 | Positive+ Negative PCB | see text | Download ExpressPCB file to order positive+negative PCB | Download PCB software from ExpressPCB and order, you get 3 boards for about $90(US). |
| 1 | Dual Positive PCB | see text | Download ExpressPCB file to order dual positive PCB | The 3 boards must be the same, so you can't order dual positive and positive/negative together. |
| 1 | SPX78 | * | Superpower voltage | SPX78, specify voltage [note that standard LM78xx can be used] |
| 1 | SPX79 | * | Superpower voltage regulator | SPX79, specify voltage [note that standard LM79xx can be used] |
| 2 | DB1,DB2 | 600VA 4A |
Genesic SiC bridge rectifier | KBL406G |
| 2 | C1, C2 | 0.01?F |
Kemet Film Capacitor 63volts 0.01uF 10% LS=5mm | SMR5103K63J01L4BULK |
| 2 | C3, C4 | 10000?F |
Nichicon Audio Grade | UKA1C103MHD |
| 1** | Transformer | Regulator Vout = dual 6V to 15V or bipolar up to +/-15V |
max 1A per supply | Triad VPT24-1040 |
| 1** | Transformer | Regulator Vout = dual 3.3V to 5V or bipolar +/-5V |
max 2A per supply | Triad VPT12-2080 |
| 1** | Transformer | Regulator Vout = dual 6V to 15V or bipolar up to +/-15V |
max 400mA per supply | Amveco 70042K |
| 1 |
Connector Plug |
Omron I/O Connectors 4P CABLE PLUG CONN 28-20 AWG | XN2A-1470 | |
| 1 |
Connector Socket |
Omron I/O Connectors 4P CABLE PLUG CONN 28-20 AWG | XN2D-1471 |
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| 2 |
R1‡, R2‡ |
Static Load Resistor |
Static load to improve transient performance |
Select a value Vout/0.015 to draw 15mA from the regulator |
| 2 |
C5‡, C6‡ | 100µF | Nichicon 50V capacitor, add this capacitor to the load circuit PCB | UVR1H101MPD |
| 1 | Heat sink | 2.5"/ 63mm, height 0.8"/ 20mm, depth 1.5"/ 37mm |
Sunetec SS314 Aluminum Black Heat Sink |
SS314 (from Hong Kong via eBay) |
| 1 | Positive+Negative Schematic | Download positive+negative supply schematic) | DipTrace Schematic for Positive+Negative Superpower supply | |
| 1 | Dual Positive Schematic | Download Dual positive supply schematic) | DipTrace Schematic for Dual Positive Superpower supply |
*For dual positive supply, get two SPX78 positive Superpower
regulators with Vout as needed.
For positive/negative supply, get one SPX78 and one SPX79.
** Order the transformer that meets your Vout and power (VA) needs.
Select transformer voltage rating (either in series or parallel) above
and close to [(Vout + 1) /√2
]. Use our Transformer
Calculator page to determine your transformer VA and voltage
needs.
Choose a transformer that fits on the PCB! For a given size, the Triad
has more VA capability.
‡ These components are not on the Superpower Supply, they are mounted on the load circuit (your DAC or preamp or mixer or whatever).