LM1875T

The LM1875T is a monolithic power amplifier integrated circuit (IC) designed for high-performance audio applications. It offers very low distortion and high-quality performance, making it an excellent choice for consumer audio systems.

Key Features and Specifications

1. High Output Power:
   • The LM1875T can deliver up to 20 watts into a 4Ω or 8Ω load when powered by ±25V supplies.
   • With an 8Ω load and ±30V supplies, it can provide over 30 watts of power.
2. Low Distortion:
   • The harmonic distortion is extremely low, with a typical value of 0.015% at 1 kHz and 20W.
3. Wide Power Bandwidth:
   • The power bandwidth is 70 kHz, allowing for a wide range of audio frequencies to be amplified with minimal distortion.
4. Protection Features:
   • The LM1875T includes protection for AC and DC short circuits to ground.
   • It also features thermal protection with a parole circuit to prevent overheating.
5. High Current Capability:
   • The IC can handle high current, with an output current limit of 4A.
6. Wide Supply Range:
   • The LM1875T operates within a wide supply voltage range of 16V to 60V.
7. Internal Output Protection Diodes:
   • These diodes provide additional protection for the output stage of the amplifier.
8. High Power Supply Rejection Ratio (PSRR):
   • The PSRR is 95dB, which helps to reject noise from the power supply and ensures clean audio output.
9. Plastic Power Package TO-220:
   • The IC is packaged in a TO-220 plastic power package, which is commonly used for audio amplifier ICs and provides good thermal dissipation.

Applications

The LM1875T is suitable for a wide range of audio applications, including:

• High-performance audio systems
• Bridge amplifiers
• Stereo phonographs
• Servo amplifiers
• Instrument systems

Additional Notes

• The LM1875T was introduced by the former National Semiconductor Corporation (now part of Texas Instruments) in the early 1990s.
• It is designed to operate with a minimum of external components, simplifying the design and assembly process.
• The amplifier’s overload protection consists of both internal current limit and thermal shutdown capabilities, ensuring reliable performance and long-lasting use.

In summary, the LM1875T is a high-performance, monolithic power amplifier IC with low distortion, high output power, and a wide range of protection features. Its wide supply voltage range, high current capability, and plastic power package make it an excellent choice for a variety of audio applications.