Mono audio subsystems extend battery life in portables

The MAX97000/1/2 family of mono audio subsystems from Maxim Integrated Products combine a high-efficiency, Class-D mono speaker amplifier with distortion limiter; a DirectDrive II Class H stereo headphone amplifier; and an ultra-low-noise, analog bypass switch.

The devices use a dual-mode internal charge pump that operates at +/-0.9 V for low signal levels and +/-1.8 V for signals that require higher output power, minimizing power consumption in applications that require high audio quality, output power, and efficiency. The MAX97000/1/2 deliver over 710 mW from a 3.7-V supply into an 8-Ω load with 87% efficiency and consume no more than 1 μA in shutdown mode.

The Class H headphone amplifier outputs a ground-referenced signal that does not require output coupling capacitors. The integrated low-noise, analog DPST audio switch allows the Class D amplifier to be bypassed to reduce power consumption.

The headphone and speaker amplifiers have independent volume control and on/off control. The 4 inputs are configurable as 2 differential inputs or 4 single-ended inputs. The speaker amplifier incorporates a distortion limiter to automatically reduce the volume level when excessive clipping occurs.

The MAX97000 is packaged in a 2.0 x 2.0-mm, 25-bump WLP with a 0.4-mm pitch; the MAX97001/MAX97002 are packaged in 2.0 x 2.5-mm, 20-bump WLP with a 0.5-mm pitch. Prices start at $0.75 for the MAX97000, and at $0.83 for the MAX97001/MAX97002 (1000-up, FOB USA).

Maxim Integrated Products, 408-530-6000, www.maxim-ic.com

Product literature:
MAX97000 information page (with link to datasheet)
MAX97001 information page
MAX97002 information page (with link to datasheet)