LM49251

LM49251 www.ti.com SNAS498A – FEBRUARY 2011 – REVISED APRIL 2013 LM49251 Stereo Audio Subsystem with Class G Headphone Amplifier and Class D Speaker Amplifier with Speaker Protection Check for Samples: LM49251 FEATURES 1 2 Class G Ground Referenced Headphone Outputs E2S Class D Amplifier No Clip Function Power Limiter Speaker Protection I2C Volume and Mode Control Advanced Click-and-Pop Suppression Micro-Power Shutdown APPLICATIONS Feature Phones Smart Phones KEY SPECIFICATIONS Class G Headphone Amplifier, HPVDD = 1.8V, RL = 32Ω – IDDQHP: 1.15 mA (Typ) – Output Power, THD+N ≤ 1%: 20 mW (Typ) Stereo Class D Speaker Amplifier RL = 8Ω – Output Power, THD+N ≤ 1%, LSVDD = 5.0V: 1.37 W (Typ) – Output Power, THD+N ≤ 1%, LSVDD = 3.6V: 680 mW (Typ) – Efficiency: 90% (Typ) DESCRIPTION The LM49251 is a fully integrated audio subsystem designed for portable handheld applications such as cellular phones. Part of TI’s PowerWise family of products, the LM49251 utilizes a high efficiency class G headphone amplifier topology as well as a high efficiency class D loudspeaker. The headphone amplifiers feature TI’s class G ground referenced architecture that creates a groundreferenced output with dynamic supply rails for optimum efficiency. The stereo class D speaker amplifier provides both a no-clip feature and speaker protection. The Enhanced Emission Suppression (E2S) outputs feature a patented, ultra low EMI PWM architecture that significantly reduces RF emissions...