LM4928SD/NOPB

LM4928SD/NOPB is a device which belongs to the family of audio amplifiers available in the market. It is typically used as an amplifier stage for wide variety of audio applications such as CD Players, Digital Audio Players, High End Headphone Amplifiers and Mobile Handsets.

It is a dual channel amplifier intended to drive medium or low-impedance stereo headphones. The specified maximum single-ended output power is usually 3mW into 30ohm loads, but can be as high as 8mW depending on power supply voltage. It can also be used for mono output configurations.

LM4928SD/NOPB is a highly integrated audio amplifier, with an integrated charge pump, allowing the use of a single 5V supply. It features an optimized power management system, providing a wide dynamic range for both output channels.

LM4928SD/NOPB is also capable of operating in Hi-Fi mode, where the output power is limited by the power supply voltage. This allows efficient use of power, while providing a low noise floor.

The core of the device is a single-ended output buffer, which consists of differential input stages, a voltage follower, and a resistor-biased Class-AB output stage. The differential input stages provide good input signal isolation and wide level control range. The internal resistor-biased Class-AB output stage delivers low distortion and low output impedance.

The output stage also features a soft-start protection circuit, which ensures protection against supply transients by limiting the max output voltage at startup, and an over-temperature and audio shutdown protection, which protects the chip from severe overloading.

The charge pump is provided to step up the input voltage to a higher level to allow the operation of the device at lower voltage levels. This allows the LM4928SD/NOPB to operate at low voltage levels with a very low quiescent power draw, making it ideal for portable audio applications.

LM4928SD/NOPB is a highly integrated, efficient and robust solution for audio amplifier needs. Its features, such as single 5V supply and low power consumption, make it an ideal choice for mobile applications. Its wide range of supported output powers can satisfy a variety of applications from headphones to mobile handsets.