LM4890SS

The LM4890SS is a Class AB audio power amplifier designed for demanding mobile phone and portable communication device applications. Operating at 5V with a 1kHz input signal, it delivers up to 2.5W of output power into a 4Ω load with less than 1% THD+N over the 20Hz to 20kHz audio frequency range. The device requires minimal external components, enabling a simple application circuit that provides high-quality output power. Its output stage requires no external coupling or bootstrap capacitors, making it ideal for low-voltage, low-power applications. The LM4890SS features a shutdown mode via a control pin for reduced power consumption, and incorporates switching noise suppression to eliminate power-on and power-off transient noise. The amplifier is unconditionally stable and unity-gain stable by design, with voltage gain adjustable through external resistor configuration for ease of use.

Applications

• Walkie-talkies
• Sound toys
• Bluetooth speakers
• Low-voltage audio systems
• Security surveillance systems

Key features

• High output power (2.5W into 4Ω load at 1kHz, THD+N<10%)
• Excellent pop-and-click suppression during power-up and power-down
• No external bootstrap capacitor required
• Unity-gain stable
• Low shutdown leakage current (typical 0.1μA)
• Wide supply voltage range: 1.8V ~ 6V
• Adjustable external gain
• Available in SOP-8 or MSOP-8 package