HT81293 lithium battery powered built-in adaptive boost 20W mono class D amplifier IC solution

HT81293 single/dual lithium battery power supply built-in adaptive dynamic boost 20W mono class D power amplifier IC solution

Since 2017, outdoor Bluetooth speakers (including 2-inch/4-inch portable Bluetooth speakers and 6-inch/8-inch outdoor pull-bar speakers) have become the fastest growing speaker category. This type of speaker is powered by a single lithium battery, and generally uses an audio amplifier chip with built-in boost. The most common amplifier chip with charge pump boost is boosted to 6.3V with a power output of 3-5W/4 ohms, and the amplifier chip with inductor boost boost is boosted to around 7V with a power output of 6-8W/3 ohms. Its performance basically meets the application requirements of indoor and outdoor scenes. However, greater power and better sound quality have always been the eternal pursuit of the speaker market.

Shenzhen Yongfukang Technology Co., Ltd. In response to the demand for sound quality and power upgrades in the trolley speaker and Bluetooth speaker market, we promote a single-cell dual-cell lithium battery powered built-in adaptive dynamic boost 20W mono Class D amplifier IC-HT81293. Using the latest BCD process, the internal Boost module boosts the voltage to 12V, which is equal to the voltage of lead-acid batteries/three-series lithium batteries, achieving the same power output of a single lithium battery supply.

The HT81293's unique adaptive dynamic boost can adjust the output voltage of the power module according to the output power required by the chip, greatly improving the battery life of the lithium battery; its input current limit function can set the maximum input current to prevent the main control from restarting due to the instantaneous voltage drop of the lithium battery (considering the power requirements, it is generally recommended to set the maximum input current to about 8A); it can switch between various modes such as shutdown, startup, and anti-crack on/off through a main control IO port, saving the resources of the Bluetooth main control; 2-speed anti-crack mode, ACF1 wide dynamic volume shock mode is suitable for outdoor pull-bar speakers, and ACF2 high-fidelity low-distortion mode is suitable for portable Bluetooth speakers. The two mode selections only require changing the peripheral resistors to present different styles of sound quality.

HT81293 Overview

The HT81293 is a mono Class-D audio power amplifier with built-in boost. When powered by a lithium battery, THD+N=10% and can continuously output 18W power (4Ω load).

The HT81293A has a built-in dynamically adjustable boost, which can provide a voltage that adapts to different output powers for the Class D amplifier, which can greatly improve system efficiency and extend battery life. The HT81293F has a built-in fixed boost, providing a fixed 9V or 12V boost for the Class D amplifier. The HT81293 can configure the boost current limit value to prevent excessive current spikes.

The biggest feature of HT81293 is the anti-clip distortion (ACF) output control function, which can detect and suppress the output signal clipping distortion (broken sound) caused by excessive amplitude of input music and voice signals, and can also adaptively prevent the output clipping caused by the drop of BOOST boost voltage, significantly improve the sound quality, create a very comfortable listening experience, and protect the speaker from overload damage. HT81293 provides two ACF modes for different music experiences, as well as ACF-Off mode. HT81293 has advanced spread spectrum function to suppress EMI. The gain of HT81293 is 32dB . In addition, HT81293 integrates output overcurrent protection, on-chip overtemperature protection, boost overvoltage protection and other functions.

HT81293 Features

・Anti-Clipping Function (ACF)

・Spread spectrum technology

・Output power:

18W (VBAT=3.7V, RL=4Ω, THD+N=10%, fIN = 1kHz)

16W (VBAT=3.7V, RL=4Ω, THD+N=1%, fIN = 1kHz)

・VBAT power supply range: 3.0V to 12V, suitable for single-cell and double-cell lithium battery applications

・High-efficiency Class H boost function - boost rail with adaptive amplifier power to extend battery playback time (HT81293A) - Adjustable maximum current limit to effectively prevent battery failure

・Protection function: Overcurrent/overheat/overvoltage protection function

・Lead-free package, ESOP16

HT81293 Applications

・Bluetooth/Wi-Fi speakers ・Portable speakers ・Smart speakers ・Smart home

HT81293 dynamic boost waveform:

HT81293 Application Information

1. HT81293 Pinout

2. HT81293 Pin Description

3. Schematic diagram of HT81293DEMO board

4. HT81293DEMO board PCB top design diagram

5. HT81293DEMO board PCB bottom design diagram

6. HT81293DEMO board patch diagram

7. HT81293DEMO Board Bill of Materials

8. HT81293DEMO board 3D layout front

9. Back side of HT81293DEMO board 3D layout diagram

10. HT81293 DEMO board physical picture