“First” closed-loop PWM-input amplifier power stage

The TAS5601 is the industry’s “first” PWM-input 20W stereo Class-D power stage with closed-loop feedback. The highly efficient power stage produces a more accurate sound, improves EMC performance, and relaxes power supply performance requirements to lower system cost. The flexible device supports multiple output configurations and includes a simple PWM interface to a video or audio processor to ease design and speed time-to-market for manufacturers of LCD, plasma and DLP TVs, and media docking stations.

Improving audio performance, the closed loop architecture of the TAS5601 enables the audio subsystem greater control over the speaker, reproducing a more accurate sound with improved bass response. The superior power supply rejection ratio (PSRR) of closed loop architectures reduces power supply noise coupling into the audio band, allowing engineers to design lower-cost power supplies. The EMC performance is also greatly improved by slowing down the output edge transitions while still maintaining excellent THD+N. The TAS5601 is more than 90 percent efficient and requires only two supplies, a 3.3V and 10V to 26V rail. Supporting operation up to +26V allows LCD TV manufacturers to power the device of the existing +24V backlight rail, eliminating the need for a dedicated audio power rail and further lowering system cost.

In addition, the TAS5601 is fully protected with integrated self-protection circuits against faults including over-voltage, under-voltage, over-temperature and short circuit. Short-circuit faults and thermal warnings are reported back to the system controller.

The flexible platform of the TAS5601 supports multiple output configurations for driving two bridge-tied speakers, four single-ended speakers, or a combination of single and bridge-tied speakers for 2.1 system support. To further simplify design and speed time-to-market, the TAS5601 includes a simple PWM interface to a video processor or a digital audio processor such as TI’s recently introduced TAS3308 audio SoC. The TAS601 is available in a 56-pin HTTSOP package.