Watford, UK Asahi Kasei Microsystems (AKM) has introduced the AK4368 , a low power stereo DAC with built-in 3D enhancement, high output headphone amplifier and PLL - all features that make it ideal for ultra-compact mobile phones, smart phones and PMPs. The 3D stereo emphasis circuit, together with the bass boost circuit give a better quality and more rounded dimension to music relayed from mobile phones. The 3D circuit can also be used to apply effects on non-digital external sources and can emphasise both headphone output, speaker output or both. Incorporating AKM's original ALC circuit, the AK4368 automatically adjusts the volume of mobile ring tones. The analogue mixing function means the side tone, beep and other analogue signals can be mixed with headphone amplifier output. The built-in stereo line output means level and volume sent to an external speaker amplifier can be adjusted independently of the stereo output. The device's PLL is compatible with various mobile phone standards and USB system clock frequencies and can generate frequencies for audio playback, making it easy to synchronize the clock with the application processor of mobile phones or smart phones. The AK4368's power management function switches the power to each circuit block on or off independently and the µP interface is 3-wire and I2C bus compatible. The wide operating voltage, ranging from 3.6 V to 1.6 V, saves on power consumption. The high performance of the AK4368 comes in an ultra-small package: the chip measures just 4 x 4mm, making it the optimum choice for mobile phones and audio playback PMPs. The AK4368 is available in a 41-pin BGA package. Evaluation boards and samples are available now. AKM Asahi Kasei Microsystems , Watford, UK. www.akm.com.
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