Product Preview EV6550DHAT (CML Microcircuits)

Product Preview
EV6550DHAT
PP/EV6550DHAT/1 December 2019 Raspberry Pi HAT for CMX655D The EV6550DHAT brings together the Raspberry Pi and the CMX655D Ultra-low Power Voice Codec in a convenient and inexpensive way, enabling easy demonstration of the CMX655D and providing improved low power audio capabilities to the Raspberry Pi. This is achieved using common hardware and open- source software, creating a platform that is easy to use and that simplifies product development.
Features
One of the major benefits of the hugely-popular Raspberry Pi is Two top-ported digital MEMS mics its low power, flexibility and accessible GPIOs which encourage developers to expand on its basic functionality. The multiway Easy screw connection for external GPIO header on the latest versions of the board consists of 40 speaker mixed-function pins, 26 of which support general purpose Flexibility to use local or off-board input/output connections. power for the PA The Raspberry Pi HAT (Hardware Attached on Top) is a hardware standard defining an add-on board that mounts directly onto the Accessible GPIO and test pads to allow Raspberry Pi and attaches to the GPIO header. The EV6550DHAT further options (e.g. external MEMS) conforms to this standard and integrates the functionality of the User-modifiable prototype space CMX655D Ultra-low Power Voice Codec into the Raspberry Pi environment. Option to add line out phono connector The EV6550DHAT enables the CMX655D’s feature set (two matched channels supporting a wide variety of digital MEMS Simple GUI with open-sourced drivers microphones, signal processing and a 1W high-efficiency Class D On-board reset button or reset via the speaker amplifier) to be easily demonstrated. The most immediate benefit is an improvement to the standard low power GUI audio capabilities of the Raspberry Pi.

Control and demonstration of the CMX655D is via the
Applications
EV6550DHAT GUI that is pre-loaded into EEPROM. The GUI Demonstrates CMX655D functionality allows for recording of wav files at 8 / 16 / 32 or 48ksps with Product development with the adjustment of input audio gain from –12dB to +3dB. Control of playback volume from –90dB to 0dB, muting and “smoothing” is Raspberry Pi also provided. There is a facility to play back 4 pre-recorded

samples at different rates to compare sample rate vs audio
Key Advantages
quality. Small, compact design Conforms to HAT definition Huge range of open source compatible software available Low cost solution EV6550DHAT 65mm x 56.5mm © 2019 CML Microsystems Plc Page 1 of 2