The KX4990 audio power amplifier from 科芯微电子 offers up to 2 W output at 5 V with low distortion and a compact MSOP/LLP package.
The KX4990 is a dual‑output audio power amplifier designed for mobile phones and portable communication devices. It operates from 2.2 V to 5.5 V and can deliver up to 2 W into a 4 Ω BTL load at 5 V without the need for external coupling capacitors.
The chip features a high PSRR, low THD+N (<0.1 % across 1‑20 kHz), sleep‑mode power reduction, and a gain‑bandwidth product of 2.5 MHz. It is available in several small‑area packages (MSOP, SOP, LLP) and includes noise‑suppression technology for clean power‑on and power‑off transitions. This manual is written in Chinese.
| Maximum output power (5 V, 4 Ω BTL) | 2 W |
|---|---|
| Total harmonic distortion + noise | <0.1 % (1‑20 kHz) |
| Gain‑bandwidth product | 2.5 MHz |
| Supply voltage range | 2.2 V‑5.5 V |
| Sleep‑mode leakage current | <0.1 µA |
| External coupling capacitor required | No |
It can deliver up to 2 W into a 4 Ω BTL load when powered at 5 V.
No, the chip’s output does not need external coupling or bootstrap capacitors.
The THD+N is less than 0.1 % across the audio band (1‑20 kHz).
The leakage current in power‑down mode is below 0.1 µA.