Stereo Audio Coder-Decoder Circuit

Stereo Audio Coder-Decoder Circuit

This is a design circuit for audio coder and decoder. This audio coder-decoder is suitable for home and portable applications like MD, CD and MP3 players. This circuit uses UDA1380 for main components. This is the figure of the circuit;

The UDA1380 is a stereo audio coder-decoder, available in TSSOP32 (UDA1380TT) and HVQFN32 (UDA1380HN) packages. All functions and features are identical for both package versions. The term ‘UDA1380’ in this document refers to both UDA1380TT and UDA1380HN, unless particularly specified. The front-end of the UDA1380 is equipped with a stereo line input, which has a PGA control, and a mono microphone input with an LNA and a VGA. The digital decimation filter is equipped with an AGC which can be used in case of voice-recording.

The DAC part is equipped with a stereo line output and a headphone driver output. The headphone driver is capable of driving a 16 W load. The headphone driver is also capable of driving a headphone without the need for external DC decoupling capacitors, since the headphone can be connected to a pin VREF (HP) on the chip.

[Circuit schematic diagram source: Phillips Semiconductor Notes]