The single-supply bridged version of the Class-D amplifier has been assembled, and I am most pleased to report that it works beautifully!

Input side of the amp

Output side of the amp

For those new to the project, a Class-D amplifier is a highly efficient amplifier that operates its output devices as switches instead of as variable resistors.  We posted a highly experimental version of this project last November, and it met with a surprising amount of positive feedback from the DIY community.  Therefore, we developed it as a formal project.

The amplifier has been converted into a single-supply version, which removes quite a bit of complexity from its power supply.  The ideal power supply used to be a custom-built bipolar supply capable of high currents, but now, an old laptop power brick that supplies 20V at a few amps is perfect.

A short demonstration video follows.  For more technical information, be sure to check out the github repository that contains a wealth of information on the development of this project.

Still remaining:  packaging the project.  I wanted to verify that everything worked before taking the time to stuff everything into a box.

UPS delivered a present today… Class-D Amplifier parts!

Shipment tracking indicates the new PCB will get here on Monday, at which point construction can begin.  Be sure to watch for news related to project development here, on the github page, and on the Flickr photostream.

Over at Dangerous Prototypes, [Ian] is designing a simple digital sampling oscilloscope.

…okay, so maybe it’s not so simple.  It features a high-speed (50MHz) ADC and an FPGA to do the actual sampling.  Their site will be detailing a different part of the design each day.  I know I do not speak only for myself when I say I could stand to learn a lot about analog electronics…

Parts for the latest amplifier revision were ordered tonight.  Total parts cost to build one two-channel board was $32.  It should theoretically be possible to get 50W per channel from this amp, so this cost is quite reasonable.

Pictures to follow once the PCBs and components arrive.

The newest version of the Class-D Amplifier PCB was ordered last night.  For a change of pace, I ordered from Advanced Circuits this time around, as this should result in a shorter lead time than my usual standby of BatchPCB.  The shorter leadtime should help this project be ready for demonstration at Maker Faire North Carolina, even though May is looking pretty busy.

A revised version of the Class-D Ampifier layout has been nearly completed. The new version features a greatly simplified power supply, higher-speed gate drivers, and a more robust modulation scheme.

This PCB still needs to undergo a peer review to help catch any potential manufacturing issues, and the silkscreen needs some touching up (adding the NBitWonder and Open Hardware logos, for instance).  The plan is to get these things taken care of and order a prototype or two very soon.

As always, the latest project development information is available in the github repository.

Tonight I finished soldering components on the PCB for VoIP32v2.  Software development will soon begin.  While I cannot guarantee speedy software development, I would like to have at least a simple networking demo ready for Maker Faire North Carolina.

More photos can be found in our Flickr stream.

Adafruit‘s [johngineer] provides a look at what engineering turns out to be for so many engineering students.  Click for the full-sized version.

Last night, I started assembling the VoIP32v2 prototype PCB.  I was able to get most of the semiconductors soldered down in addition to their crystal oscillators.  Then my soldering iron tip picked up a coating of melted plastic from somewhere; I think I held it too close to the roll of solder wick I used to clean up along the way.

Assembly will progress in the coming days, as soon as I find a new soldering iron tip.  Be sure to follow the project in its github repository and in the forums.

The bare PCBs for VoIP32v2 arrived yesterday.  Watch the forum, the github repository, and this space for further developments!