STMicroelectronics' combined audio converter/driver IC

SINGAPORE: Audiophiles and aficionados of portables entertainment devices such as MP3 players, cellular phones, personal computers, laptop computers and/or PDAs are extremely demanding about the sound quality of their entertainment experience.

Meanwhile, engineers behind the scenes continue to struggle with delivering increasing quality with new features in more stylish packaging at lower cost.

Combined audio converter/driver ICs are simplifying the design of set-top boxes and other consumer audio/video products, but the new TS4657 from STMicroelectronics, a leading provider of digital audio ICs, improves on existing technology by reducing external components and power consumption and improving sound quality.

ST’s new TS4657 is a single chip combining audio-DAC (digital-to-analog converter) and line-driver functions to feed the audio Line-Out connection of set-top boxes, DVD players, portable multimedia devices, sound cards, or similar equipment. The Line Out provides a direct connection to drive an external home amplifier, allowing for a better audio experience by maintaining constant signal levels, better digital volume control and a wider volume range.

The IC uses an internal power management unit to produce a 2.2Vrms audio-output signal for voltages from 3.0V to 5.5V, eliminating the need for a separate high-voltage power supply to drive the Line-Out output. Similar devices typically require four external capacitors for the charge pumps but ST’s high-frequency design integrates this function on-chip, thereby saving board space and bill-of-materials costs.

The TS4657 is in production now, available in the 4 x 4mm QFN20 package and priced at $0.91 in quantities of 1,000 units.