Analogue switch enhances audio quality

Austriamicrosystems has expanded its analogue switch portfolio with the AS1747, a dual SPDT (single-pole/double-throw) low-voltage analogue signal switch.

The AS1747 is optimised for audio and can handle negative signals with a single positive power supply.

The switch, which is the first within a range of switches with negative signal capability, allows designs without AC coupling capacitance in audio applications.

'Switches that are able to handle negative swings like the AS1747 are an ideal match for low-power, negative-swing capable audio amplifiers to achieve high-quality audio performance,' said Walter Moshammer of Austriamicrosystems.

'This system actually improves signal quality by removing the AC coupling capacitors of the speaker, the primary source for audio pop noise.

'It has a longer battery lifetime, higher signal amplitude and also reduces space.' The AS1747 combines the low on-resistance of 0.4ohm with a channel-to-channel matching of less then 0.03ohm, reducing the amount of signal deviations between channels to a minimum.

Additionally, the AS1747 shows an on-resistance flatness of 0.25ohm.

This improves total harmonic distortion (THD+N) to 0.01 per cent and yields an excellent audio signal quality.

The AS1747 can handle negative signals with a single positive 1.8V to 5.5V power supply and is available in a 10-pin, TDFN(3x3mm) package suitable for operating environments ranging from -40 to +85C.

Back to top