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.