Monday, February 20, 2012

4 input headphone amplifier with TPA6120 chip

I already have schematic and PCB design with TPA6120 chip with 2 inputs. Now I made same design but with 4 inputs and one line output. The new design contains PCB transformer, dual +/- 15V power supply, 4 channel mixer without preamplifiers, unbalanced/balanced converters, and line output with level adjustment.

The schematic:

The device contains 4 audio inputs with volume adjustment. The input connector must be soldered to the bottom of PCB (blue) and the volume must be potentiometers soldered to the top (yellow) of PCB. The input and line output connectors can be 6.3mm jack OR stereo RCA connector. The headphone output can be 6.3mm jack only. The PCB contains header for 4 power filter circuits (whats are optional if not required) for 4 dual operational amplifiers. The operational amplifier chips are compatible with TL072 for cheapest solution, NE5532 for better quality, and with LT1124 for the best quality. These chips used for the input mixer, for unbalanced/balanced converters, and for the line output amplifiers.

The PCB design:

See also:

PCB sales of this project
Module name Size
PDF SCH PCB image Tested Price (US$)
Des. Sim.1 Full2 Sim.1 Full2 Man3
4 input headphone amplifier
189x112 212 No
Yes Yes - - No 30
39 Ask
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  1. Nice stuff!I am really impressed by way of presenting your great work.Awesome keep it up...pcb suppliers

  2. The PCB design images displayed in your post are looking amazing, thx for sharing.