Texas Instruments Incorporated (Dallas, Texas) has introduced a 15W Class-D audio amplifier for driving bridged-tied stereo speakers with integrated electromagnetic interference (EMI) suppression technology that eliminates the need for inductor-based output filters, thus considerably reducing the bill of materials for system integrators. Instead, cheaper ferrite bead filters can be used, which also reduces board space.
The TPA3110D2 boasts what TI terms as SpeakerGuard protection - circuitry with an adjustable power limiter and a DC detection circuit that protects speakers from damage. Speakers down to 4 can be driven using this part, making it well suited to consumer audio applications that include HDTVs, media docking stations and sound bars. A very low THD+N performance of < 0.1% THD+N over the full power range at 1 kHz, plus the click-and-pop suppression, suggests that the TPA3110D2 doesn't compromise audio fidelity.
With an efficiency of 90% claimed for the TPA3110D2, TI says there's no need for an external heat sink. Notably, the low-through pin-out makes layout simpler and optimises thermal performance, with the high-voltage pins on one side and input and control pins on the other. Other features include a wide supply voltage range (from 8 to 26V), an auto-recovery feature and protection against shorts to GND, VCC, and output-to-output (see the datasheet for more details).
The TPA3110D2 is available now in a 28pin TSSOP package. Other members of the TPA311xDx family comprise the TPA3111D1, TPA3112D1 and TPA3113D2 " 10 and 25W mono amplifiers, and a 6W stereo amplifier respectively. All there will be available in late 3Q 2009.
Related design articles:
Designing with Class D amplifier ICs
Class D amplifier FAQ - Part 1: Overview, amplifier selection and filters