Audio Subsystem Family Adds Two Members

Extending the company’s family of low-power Boomer Class D audio subsystems, the LM49352 mixed-signal audio subsystem and LM49151 analog subsystem target smart phones, full-featured phones, portable gaming devices, and portable GPS devices. The LM49352 integrates audio codec functionality with ground-referenced headphone amplifiers, an earpiece driver, a Class D loudspeaker, and an audio DSP in one miniature 3.3 mm x 3.3 mm package. The loudspeaker delivers an efficiency of 93% at 970 mW from a 4.2V supply while the headphone amplifier consumes 18 mW of power. The LM49151 analog subsystem integrates an earpiece driver, Class D loudspeaker, ground-referenced headphone amplifiers, and automatic level control (ALC) in a 2.2 mm x 2.6 mm package. It consumes 7.3 mA of quiescent current at 3.3V for the loudspeaker and headphone. The subsystem’s ALC provides a variety of options to control audio distortion levels and prevent speaker damage. Available now, prices for the LM49352 and LM49151 are $7.55 and $1.60 each/1,000, respectively. NATIONAL SEMICONDUCTOR CORP., Santa Clara, CA. (800) 272-9959.