Date: 15/11/2008

Noise-free class-AB audio amplifier for portable and wireless applications

ON Semiconductor introduced the NCP2991, a new generation of Class AB audio amplifier dedicated to provide high audio performance without sacrificing power efficiency for portable and wireless applications. The NCP2991 provides noise-free audio amplification and fast response time.

Some of the features include:

1. NCP2991 offers a Power Supply Rejection Ratio (PSRR) of -103 decibels (dB) that eliminates any noise that may be generated by the fluctuation of battery supply voltage.
2. The device is highly resistive to the so-called "TDMA noise" (Time Division Multiple Access) that occurs during the Global System Mobile (GSM) transmission.
3. The device guarantees zero pop-and-click noise at start-up and shutdown, which apply to all input configurations.
4. Its very low typical Total Harmonic Distortion (THD) level (0.015 percent) ensures high fidelity audio output.
5. Provides fast audio response. The start-up time of NCP2991 is selectable between 15 milliseconds (ms) and 20 milliseconds (ms).
6. The NCP2991 can be kept in shutdown mode when it is not in use. Therefore, most of the time, the NCP2991 consumes only 20 nanoamps (nA).
7. The NCP2991 is capable of delivering 1.35 watts (W) of output power to an 8-ohm speaker, or 1.1 W to a 4-ohm speaker.
8. It also has built-in thermal overload protection circuitry to disable the device's operation in case of an over-temperature situation.

Packaging: µBump package
Size: 1.45 mm x 1.45 mm x 0.6 mm
Pricing: priced at $0.22 USD per unit in 3K unit quantities

For more information, visit www.onsemi.com