Asahi Kasei Microsystems (AKM) introduced the AK4631 , a tiny, low-power consumption 16 bit mono A/D and D/A audio converter for digital still cameras and voice recorders. The AK4631 Audio CODEC features built-in microphone and speaker amplifiers and automatic level control.
It succeeds the AK4536, which has been widely used for audio processing in digital still cameras. The AK4631 is compatible with speaker amplifiers with working voltages up to 5 V. This means that piezoelectric speakers, used in slim equipment, can be driven directly with no need for an external amplifier. The circuit comes in a 28-pin QFN package (5.2 mm square), which is interchangeable with the AK4536 or a super-small 41-pin BGA (4 mm square) package, which reduces the mounting area by 40%. The AK4631 incorporates AKM's unique microphone auto level control circuit, a digital volume control and beep input, and speaker amplifiers compatible with both dynamic and piezoelectric speakers. The built-in automatic level control circuit improves speaker output power and the internal register is switchable for a power saving mode. With built-in PLL, the AK4631 generates the necessary audio clock internally, enabling simple interfacing with the system LSI. The CODEC offers sampling rates from 7.35 kHz to 48 kHz and an operating voltage range from 2.6 to 36 V. Evaluation boards and samples are available now. AKM Asahi Kasei Microsystems , WD1 8YH Watford, UK.www.akm.com