If your project has limited visual I/O or processing, this solution can enable high quality audio to be generated from easily accessed . Mp3 files stored on an SD card. The DSP hardware processing the c ompressed audio files in real time, while freeing the control processor for other tasks. As files are stored on a standard SD card, generating/editing/updating (for instance for other language variants) is a straightforward task. Development is speeded up using this proven hardware which has been through CE certification. manufactured in groups of 4.
The PCB measures 80x42mm and can be rear mounted to a custom front panel membrane keyboard PCB (type up to 9 keys and up to 5 LED indicators).
Project Background:
MKC started to source components at the initial hardware design stage to ensure that no long lead time components were being designed in. By coordinating the manufacturing phase whilst product development was underway we were able to deliver productio hardware at the 12 week deadline.
Our solution uses a high-performance, low-power DSP based system capable of reading and decoding the .MP3 input dat astream at high bitrates. Using an 18-bit over sampling, multi-bit, sigmadelta digital to analog convertor at the output stage ensures a high quality stereo audio output with no phase error between L/R channels.
Software controlled volume levels for L & R outputs is supported if needed.
An Atmel AVR single chip processor takes care of the user keypad inputs, LED indicators on the front panel, control of the decoder and output audio signal routing to one of 2 stereo outputs.
Source files are encoded in Mp3 format (up to 320k bit rate), Also supported: WMA, AAC, AAC+, Ogg Vorbis, FLAC and MIDI A Standard size SD card socket fitted on the PCB, supporting FAT16* (*NTSC file format not supported).
2x Stereo 3.5mm jack sockets for A + B audio output
2,1mm power jack for 5v power
Header for ISP and serial downloading of code (processor & DSP)
Power requirement – 5v D.C (An on board regulator provides the 4 different voltage rails required and a voltage monitor ensures that the unit will always reset reliably after a power rail interruption).
Information provided as an example only, most solutions are custom designed for your application so please get in touch for more in depth technical information or a quotation for a particular project.
Look 
Flexible Membrane Keypads
PCB Membrane Keyboards
Backlit Membrane Switches
Capacative Touch Panels
Rugged Front Panels
Silicone Rubber Keypads
Graphic Overlays & Labels
Standard & Custom Displays