Inside a compact class D amplifier (Patreon)

Inside a 360W digital amplifier

I bought this amplifier purely so we could open it and take a look inside. It's a modern class-D amplifier that uses pulse width modulation and filtering to achieve high power audio amplification efficiently with low heat and size. Initially I thought it might have a dedicated chip or module for the amplification, but it seems to use discrete transistors on the output with a couple of mystery chips. The power supply is notable for using a discharge lamp ballast drive chip, presumably because it is a dual rail power supply with the zero volt output referenced to mains ground. The way the four output transistors are pinned down onto the aluminium backplate is quite interesting. The areas of most concern for reliability are the ribbon cables and the solder joints on the speaker pillar terminals I'd rather the power had been linked across with a beefier dedicated wiring loom. The unit has three operational modes:- Stereo - independent left and right channels. Parallel - One input fed to both channels (mono) Bridged - One input fed to both channels in antiphase to drive one speaker at higher power. The "ground lift" option just isolates the incoming signal cable screen from the chassis. Do not ever disconnect the mains earth/ground. This amplifier was bought from CPC in the UK. https://cpc.farnell.com/pulse/pla2180d/19-1u-amplifier-class-d-2x-180w/dp/DP36607 Note that I've not tested the audio performance of this amplifier. If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- https://www.bigclive.com/coffee.htm This also keeps the channel independent of YouTube's algorithm quirks, allowing it to be a bit more dangerous and naughty. #ElectronicsCreators