1FEATURES

2• Passes FCC Class B Radiated Emissions with

20 inches of cable

• E2S System Reduces EMI while Preserving

Audio Quality and Efficiency

• Output Short Circuit Protection with Auto-

Recovery

• Stereo Class D Operation

• No Output Filter Required

• Internally Configured Gain (12dB)

• Synchronizable Oscillator for Multi-Channel

Operation

• Low Power Shutdown Mode

• Minimum External Components

• Click and Pop Suppression

• Micro-Power Shutdown

• Available in Space-Saving WSON Package

APPLICATIONS

• Mobile Phones

• PDAs

• Laptops

KEY SPECIFICATIONS

• Efficiency at 3.6V, 400mW into 8Ω 85% (typ)

• Efficiency at 5V, 1W into 8Ω 88% (typ)

• Quiescent Power Supply Current at 5V 3.2mA

• Power Output at VDD = 5V, RL = 4Ω, THD+N ≤

10% 2.6W (typ)

• Power Output at VDD = 5V, RL = 8Ω, THD+N ≤

10% 1.6W (typ)

• Shutdown current0.01μA (typ)

DESCRIPTION

The LM48310 is a single supply, high efficiency,

mono, 2.6W, filterless switching audio amplifier. The

LM48310 features TI’s Enhanced Emissions

Suppression (E2S) system, that features a unique

patent-pending ultra low EMI, spread spectrum, PWM

architecture, that significantly reduces RF emissions

while preserving audio quality and efficiency. The E2S

system improves battery life, reduces external

component count, board area consumption, system

cost, and simplifying design.

The LM48310 is designed to meet the demands of

portable multimedia devices. Operating from a single

5V supply, the device is capable of delivering 2.6W of

continuous output power to a 4Ω load with less than

10% THD+N. Flexible power supply requirements

allow operation from 2.4V to 5.5V. The LM48310

offers two logic selectable modulation schemes, fixed

frequency mode, and an EMI suppressing spread

spectrum mode. The E2S system includes an advanced, patent-pending edge rate control (ERC)

architecture that further reduce emissions by

minimizing the high frequency component of the

device output, while maintaining high quality audio

reproduction (THD+N = 0.03%) and high efficiency (η

= 88%). The LM48310 also features a SYNC_IN input

and SYNC_OUT, which allows multiple devices to

operate with the same switching frequency,

eliminating beat frequencies and any other

interference caused by clock intermodulation.

The LM48310 features high efficiency compared to

conventional Class AB amplifiers, and other low EMI Class D amplifiers. When driving and 8Ω speaker

from a 5V supply, the device operates with 88%

efficiency at PO = 1W. The gain of the LM48310 is

internally set to 12dB, further reducing external

component count. A low power shutdown mode

reduces supply current consumption to 0.01μA.

Advanced output short circuit protection with autorecovery

prevents the device from being damaged

during fault conditions. Superior click and pop

suppression eliminates audible transients on powerup/

down and during shutdown.