Yesterday, we got the boards back from the PCB fab house. Today, I built the FAB1215 prototype and tested it.  Now, we have a power supply to power all our FAB modules. Yay!

This convenient power supply is powered by a simple 12VDC power adapter (wall wart). The one I’m using is rated 400mA and it’s the only one I can scrounge around… but I’d recommend a 1Amp power adapter so you have plenty of power to spare.

The +/-15Volts is generated by an off-the-shelf part, and the +48Volts for phantom power is generated by our DC-1248 Module (12VDC to 48VDC converter).

The FAB1215 has (1) DC jack to accept the 12Volts input, and (2) IDC headers that route +/-15Volts, and +48Volts so you can power (2) channels of your project.  The +/-15V is rated up to 190mA, and the 48Volts is rated up to 60mA  (this 60mA figure may change once I finalized on the component values and complete testing).  You simply hookup power using 10-pin ribbon cables to your FABs. It’s that easy.

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I’ve been testing the DC-1248 (12Volts to 48Volts Phantom Power) the past few days now, and I was able to further improve performance by reducing ripple down to 128mV, for a 47.7Volts output, fully loaded drawing at 57mA.  Efficiency is computed to be at 76% at this loading.

I reduced the ripple by adding another 0.1uf ceramic and 47uf electrolytic capacitor to the DC-1248 output terminals.  Since there is no more space on the DC-1248 board (measuring only 1″x1″), I added these parts to our FAB1215 PSU Module.  So here’s the new Rev.B design.

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I got my prototype boards for my DC-1248 (12Volts to 48Volts DC-DC Converter).  Quickly built a prototype, and nervously turning on the power, there was no smoke, fyring bacon sound, or anything getting hot.  Yey! So far so good… Measured the output voltage and it was 48.2 Volts. Nice.

I began loading the DC-DC converter and looking at it’s ripple waveform on my scope. Happy to say that performance improved significantly just by moving it from a breadboard into a properly designed PCB!  The board is a tiny 1″x1″ square, with (4) Millmax pins so you can easily plug-it in to our FAB1215 Power Supply Board.

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Our next board up for prorotyping is our FAB1215 Module. This is a Power Supply Module, which accepts a 12V DC input, and provides a +15V, -15V, and +48V output voltages to power your project.

The +15V and -15V will be provided by a DC-DC converter, which can provide up to 190mA per voltage rail.  The 48Volts will be provided by a FiveFish Audio DC-1248 module (12V to 48V) which can provide up to 30mA (UPDATE: Received the DC-1248 prototype boards and testing shows) 60mA maximum @ 48Volts.

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