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FS: TPA3251 amplifier complete or board


Build two of those for a friends new house, but later we used another solution as he needed much more power.

What it is:
TPA3251 based class-D amp with balanced and unbalanced inputs, analogue power supply with 100VA transformer, supply voltage around 35VDC. Case is about 280 x 280 x 60 mm (mini size).

Design of the PCB layout of the amplifier part follows TI reference design closely, to power opamps uses DC-DC +/- 15V with LDO post regulators.

Opamps are LM4562, output inductors are 10uH. Amp has speaker protection with relays (driven by fault signal from chip)

I will include the schematics and PCB layout.

See my post in the TPA3251 thread for measurements. This is 100% working and measures like TI reference board.

Unusual way of speaker output was because I used a case of a headphone amp. Cables you see in the picture are included.

Price complete unit as in the pictures: [SOLD], can also sell complete PCB board only, PM me for details. I also have additional empty PCB's [$25 incl. shipping}


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