Tiny 24bit DACs target portable audio devices

Asahi Kasei EMD Corp. launches the latest addition to its Audio2go product family, the AK4370 and AK4371 ultralow power 24bit DACs with integrated high output headphone amplifiers for cellphones, smart phones and PMPs.

AK4371 incorporates a PLL, supporting external BICK and LRCK as clock sources, in addition to support for cellphone standards and USB system clock frequencies. This makes it easy to synchronize the DAC with an application processor without a master clock.

Both AK4370 and AK4371 devices feature built-in analog and digital headphone volume controls. They also include four and six differential analog inputs respectively, which can be internally mixed and which eliminates the need for external switches. Moreover, AK4371 feature an integrated 600Ω mono drive amplifier making it suitable for hands-free operation requirements. AK4370 and AK4371 achieve an ultralow power consumption of 6.8mW at 1.8V, providing significant power saving and extending music playback time for battery operated equipment.

The power management functions, volume control and analogue mixing function are controlled via a flexible three-wire, or I2C bus interface. The minimum supply voltage of 1.6V saves power consumption and makes it easy to interface with a processor. The built-in voltage reference in the AK4371 provides a high tolerance to power-supply noise.

AK4370 is available in a small 24pin QFN (4mm?) package while AK4371 is available in 32-pin QFN housing. Evaluation boards and samples are available now.