LM1875 Audio Amplifier

The LM1875 Audio Amplifier is a monolithic audio power amplifier IC in a 5-pin TO-220 package. It delivers 20 W into a 4 Ω or 8 Ω speaker from ±25 V supplies with very low distortion, and it has built-in short-circuit and thermal protection. It is a classic choice for DIY hi-fi amplifiers, active speakers and subwoofer projects.

LM1875 Audio Amplifier Specifications

• Type: audio power amplifier IC
• Output power: 20 W into 4 Ω or 8 Ω at ±25 V; over 30 W into 8 Ω at ±30 V
• Supply voltage: 16 V to 60 V total (for example ±8 V to ±30 V)
• Distortion: 0.015% typical at 1 kHz, 20 W
• Output current: up to 4 A
• Protection: AC and DC short circuit to ground, thermal shutdown
• Package: TO-220, 5 pins

LM1875 Audio Amplifier Applications

• Mono or stereo hi-fi amplifiers (one IC per channel)
• Active speakers and studio monitors
• Subwoofer and guitar practice amplifiers
• Repairing amplifier boards that use the LM1875
• Audio electronics courses and labs

What's in the Box

• 1 × LM1875 audio amplifier IC (TO-220)

Tip: Mount the LM1875 on a heatsink, as it gets hot at full power. Its metal tab is connected to the negative supply pin, so use an insulating pad and washer when the heatsink is grounded, and keep the input and feedback wiring short to avoid oscillation.

Orders placed before 14:00 are ready for pickup the same day. Delivery across Lebanon usually takes 1–3 working days.