FEATURES

23• Ground Referenced Outputs – Eliminates

Output Coupling Capacitors

• Common-Mode Sense

• Ultra-High PSRR

• I2C Volume and Mode Control

• High Output Impedance in Shutdown

• Differential Inputs

• Advanced Click-and-Pop Suppression

• Low Supply Current

• Minimum External Components

• Micro-Power Shutdown

• Available in Space-Saving 16-Bump DSBGA

Package

APPLICATIONS

• Mobile Phones

• PDAs

• Notebook PCs

• Portable Electronic Devices

• MP3 Players

KEY SPECIFICATIONS

• Output Power/Channel at VDD = 3.6V

– RL = 16Ω, THD+N ≤ 1%: 35mW (typ)

• Output Power/Channel at VDD = 3.6V

– R L = 32Ω, THD+N ≤ 1%: 40mW (typ)

• Quiescent Power Supply Current at 3.6V:

3.5mA (typ)

• PSRR at 217Hz: 110dB (typ)

• Shutdown Current: 0.06μA (typ)

DESCRIPTION

The LM48822 is a single supply, ground-referenced

stereo headphone amplifier designed for portable

devices, such as cell phones, where board space is

at a premium. The LM48822 features TI’s ground-

referenced architecture, which eliminates the large

DC blocking capacitor required by traditional

headphone amplifiers, saving board space and

minimizing system cost.

The LM48822 features common-mode sensing that

corrects for any differences between the amplifier

ground and the potential at the headphone return

terminal, minimizing noise created by any ground

mismatches.

The LM48822 delivers 35mW/channel into a 16Ω

load with <1% THD+N with a 3.6V supply. High

power supply rejection ratio (PSRR), of 110dB at

217Hz, allows the device to operate in noisy

environments without additional power supply

conditioning. Flexible power supply requirements

allow operation from 2.4V to 5.5V. The LM48822 has

a differential inputs for improved noise rejection. High

output impedance in Shutdown mode, combined with

a charge pump-only mode allows the LM48822's

outputs to be driven by an external source without

degrading the source signal. Additionally, the

LM48822 features a 64-step I2C volume control and mute function. The low power Shutdown mode

reduces supply current consumption to 0.06μA.

Superior click and pop suppression eliminates audible

transients on power-up/down and during shutdown.

The LM48822 is available in an ultra-small 16-bump

DSBGA package (2mmx2mm).