LM4871S

The LM4871S is a Class AB, mono, bridge audio power amplifier with shutdown mode. At 1KHz input and 5V supply voltage, the maximum output power is: 3W (4Ω load, THD<10%) and 2W (4Ω load, THD<1%); THD+N is less than 1% across the audio range (20Hz–20KHz). The application circuit is simple, requiring only a minimal number of external components to deliver high-quality output power. No external coupling capacitors, bootstrap capacitors, snubber networks, or feedback resistors are required at the output. Housed in an SOP-8 package, it is particularly suited for low-power, compact portable systems. Power consumption can be reduced by enabling shutdown mode via control input, and an internal thermal shutdown protection mechanism is built in. Operation is stable with unity-gain stability. The amplifier's voltage gain can be adjusted by configuring external resistors, facilitating ease of application.

Applications

• Laptop
• Desktop computer
• Bluetooth speaker
• Low-voltage audio system

Key features

• High output power (4Ω load, 1KHz): THD+N<10% (3W), THD+N<1% (2W)
• Low shutdown leakage current: 0.6μA (typical)
• Externally adjustable gain
• Unity-gain stable
• Wide supply voltage range: 2.2V ~ 6V
• No coupling capacitors, bootstrap capacitors, or snubber networks required
• SOP-8 package