The LM4890 is an audio power amplifier primarily designed for demanding applications in mobile phones and other portable communication device applications. It is capable of delivering 1 watt of continuous average power to an 8? BTL load with less than 1% distortion (THD+N) from a 5VDC power supply.

Boomer audio power amplifiers were designed specifically to provide high quality output power with a minimal amount of external components. The LM4890 does not require output coupling capacitors or bootstrap capacitors, and therefore is ideally suited for mobile phone and other low voltage applications where minimal power consumption is a primary requirement.

The LM4890 features a low-power consumption shutdown mode, which is achieved by driving the shutdown pin with logic low. Additionally, the LM4890 features an internal thermal shutdown protection mechanism.

The LM4890 contains advanced pop & click circuitry which eliminates noises which would otherwise occur during turn-on and turn-off transitions.

The LM4890 is unity-gain stable and can be configured by external gain-setting resistors.

• Available in Space-Saving Packages: DSBGA, VSSOP, SOIC, and WSON
• Ultra Low Current Shutdown Mode
• BTL Output Can Drive Capacitive Loads
• Improved Pop & Click Circuitry Eliminates Noises During Turn-On and Turn-Off Transitions
• 2.2 - 5.5V Operation
• No Output Coupling Capacitors, Snubber Networks or Bootstrap Capacitors Required
• Thermal Shutdown Protection
• Unity-Gain Stable
• External Gain Configuration Capability

Key Specifications

• PSRR at 217Hz, VDD = 5V (Fig. 1): 62dB(typ.)
• Power Output at 5.0V & 1% THD: 1W(typ.)
• Power Output at 3.3V & 1% THD: 400mW(typ.)
• Shutdown Current: 0.1μA(typ.)