AKM Semiconductor has introduced the AK4675 stereo codec with a built-in microphone amplifier, receiver amplifier, cap-less headphone amplifier and stereo audio class-D speaker amplifier. The device also features a dual PCM interface in addition to an audio interface to allow easy interfacing in mobile phone designs with a Bluetooth interface.
The PCM interface block includes an integrated SRC that enables asynchronous mixing of audio and PCM data. The speaker amplifier includes an ALC (Automatic Level Control) circuit that can automatically adjust the recording volume of a microphone or the output volume of music source for mobile phone ring tones.
Other features include a five-band equalizer, a power supply management function enabling control of circuits block by block, and a stereo emphasis circuit designed to enhance the stereo effect by expanding the stereo sound when the audio is played on devices with extremely small speakers, such as mobile phones.
The microprocessor control interface supports the I2C bus. The sampling frequency ranges from 8 kHz to 48 kHz (PCM: 8 kHz) and operating voltage ranges from 2.2 to 3.6 V for the analog section, from 1.6 to 3.6 V for the digital section, and from 3.0 to 5.5 V for the headphone and speaker amplifiers.
The AK4675 is available in an 5.5 x 5.5-mm 83-pin BGA package. Evaluation boards and samples are available now.
AKM Semiconductor, 408-436-8580, http://www.akm.com/
AK4675 data page
AK4675 datasheet (PDF)