Stereo analogue subsystem has class G headphone amp and loudspeaker protection
National Semiconductor has introduced what it claims is the industry's first stereo analogue subsystem with integrated Class G headphone amplifier and automatic level control for smartphones and feature phones.
According to the company, the PowerWise LM49251's Class G headphone amp dynamically reduces the supply voltage to lower power consumption and extend audio playback time. The loudspeaker's automatic level control is optimised to provide designers with several options to control audio distortion levels and prevent speaker damage. According to National, it also provides designers with a programmable output power limiter for speaker protection and clip level select.
Housed in a 2.55 x 3.02mm package, the subsystem is designed to consume less than 7mA of quiescent current at 3.3V for the loudspeaker and headphone, which National claims is the lowest power consumption in its class.
