TPA3126 Class-D Amp 24V 3.5mm Jack Input (70mm x 52mm)

This is a project based on the TI TPA3126 amplifier chip. The design is based on the reference design in the datasheet and the layout of the evaluation board. Setup for 24V input, 26db gain 400khz switching frequency, and master mode. Notionally capable of 30W per channel at 1% THD.

A heatsink is required. Part number ATS-TI 10 OP-521-C1-R1 available from DigiKey and other suppliers. All other components are available through JLCPcb and/or LCSC. The shielded output inductors are not currently stocked and you must pre-order them for fabrication, but are generally available.

3.5mm stereo jack input with a 24V pass through. The 470uF bulk cap on the input is not added to the BOM as it is not known if it is required.

An extra anti-pop circuit is included that creates an ~1s delay in the rise time to 2V on the SDZ pin to keep the outputs Hi-Z (disabled) until the power supply stabilizes.

The board is relatively small at only 52x70mm. This concept is designed to build a multi-zone home amplifier system through the use of a 24V 300W power supply for 6 zones. The amplifier is notionally rated at 30W per channel for 8ohm speakers at < 1% THD. This is not yet been verified.