STA381BW - 2.1-Channel Digital Audio Amplifier | STMicroelectronics
料号： STA381BW ✓ 量产中STA381BW 概述
A digital audio amplifier is an audio IC that accepts a digital audio stream, performs signal processing and amplification, and drives speakers or line-level outputs with high efficiency. In the broader power-management and signal-processing hierarchy, the STA381BW combines a digital audio processor, Class-D-style digital power amplification, headphone circuitry, and integrated speaker-output functionality to reduce the component count of a 2.1-channel audio system.
The STA381BW is designed to deliver up to 2 x 20 W into 8-ohm speakers at an 18 V supply in the 2.0-channel BTL configuration described by STMicroelectronics application note AN3959. This output capability makes it applicable to compact home-theater, multimedia, active-speaker, and digital active-speaker products. Its integrated headphone and 2 Vrms line outputs also allow the same device to support additional listening paths without a separate output amplifier for every function.
The 2.1-channel architecture supports integration of a stereo or multichannel digital source, sound-field processing, and two amplified speaker channels. Digital processing and control through I2C allow host software to configure the device address and operating behavior. The integrated FFX power stage is intended to improve conversion efficiency and reduce power dissipation compared with a conventional linear output stage, particularly when the output voltage swing required by the speaker load is relatively low.
The VQFN-48 package requires careful PCB layout because its exposed thermal area provides the principal heat-transfer path from the power stage. Input, output, supply, and ground connections must follow the manufacturer layout guidance, while decoupling should be placed close to the relevant pins. The application note identifies a 2.0-channel BTL demonstration board based on the STA381BW and STA381BWS, providing a useful reference for power routing, speaker connections, control interfacing, and thermal implementation.
Design trade-offs include the 26 V operating limit, the 30 V absolute maximum rating, and the thermal requirements of a high-power multichannel amplifier. Designers should verify the maximum transient supply voltage, configure protection for exposed speaker outputs, and confirm that the PCB copper and thermal pad support the intended continuous output power. This page consolidates the verified product capabilities, application-note data, source links, and engineering considerations into a structured guide for evaluating the STA381BW in digital active-speaker designs.
直接替换替代料： STA381BW ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
该产品暂无直接替换替代料。
请求替代料STA381BW 最大额定值与电气特性
| Product Type | 2.1-channel high-efficiency digital audio system |
| Architecture | Digital audio processing, digital amplification, and FFX power output stage |
| Number of Amplified Channels | 2.1 channels |
| Supply Voltage Operating Range | 0 V to 26 V |
| Absolute Maximum Supply Voltage | 30 V |
| 2.0-Channel BTL Output Power | 2 x 20 W into 8 ohm at 18 V |
| Line Output | 2 Vrms |
| Headphone Output | Integrated headphone output |
| Digital Audio Interface | Digital audio streaming input |
| Control Interface | I2C |
| Selectable Device Address | Yes |
| Power Output Stage | FFX power output stage |
| 封装 | VQFN-48, 7 x 7 mm |
| 安装类型 | Surface mount |
| 输出配置 | 2.0-channel bridge-tied-load configuration documented by AN3959 |
STA381BW vqfn-48, 7 x 7 mm 引脚配置指南
STA381BW（vqfn-48, 7 x 7 mm 封装）的引脚配置。 该模拟元件具有输入、输出和电源引脚。请参阅制造商数据手册以了解失调调零、补偿和使能引脚配置。适用于信号调理和放大器电路。
暂无详细引脚数据： STA381BW.
请参阅 数据手册 以查看完整引脚配置。
典型应用
STA381BW 适用于 6 应用s: 2.1-Channel Home Theater, Digital Active Speakers, Multimedia Speaker System, Headphone and Line-Output Hub, Compact Stereo Power Amplifier, Digital Audio Processing Platform.
2.1-Channel Home Theater
The STA381BW fits a compact home-theater amplifier because it combines a digital audio engine, a high-efficiency FFX power output stage, headphone output, and 2 Vrms line outputs in one VQFN-48 device. STMicroelectronics documents up to 2 x 20 W into 8-ohm loads at 18 V in a 2.0-channel BTL configuration, making the architecture useful when the source already supplies a digital audio stream. The design can use the processed digital signal for two amplified speaker channels while retaining line and headphone paths for additional listening zones. The key trade-off is that the 26 V operating range requires careful supply regulation, and the high-output configuration demands adequate thermal-pad copper and verified speaker protection.
推荐
Digital Active Speakers
The STA381BW is suitable for digital active speakers that receive an audio stream over a digital interface and need efficient amplification close to the driver. Its integrated processing and amplification paths reduce the need for a separate codec, DSP, and power-amplifier chain, while the documented output of up to 2 x 20 W into 8 ohms at 18 V provides a useful reference for speaker-drive capability. The designer should verify supported digital formats, configure the device through I2C, and reproduce STMicroelectronics reference-layout practices for the exposed thermal area. The main engineering consideration is balancing output power against board area and heat dissipation.
推荐
Multimedia Speaker System
The STA381BW can serve as the central audio IC in a multimedia speaker system that accepts digital audio and requires amplified stereo outputs plus flexible monitoring or auxiliary connections. Integrating the headphone path and 2 Vrms line output alongside the FFX power stage allows several output uses to be consolidated in a VQFN-48 package. This is particularly useful where enclosure space is limited and a separate analog input path would otherwise require additional circuitry. System-level validation must confirm that the digital source format is accepted, that the I2C address can coexist with other bus clients, and that the power supply remains within the 26 V operating range during startup and load transients.
推荐
Headphone and Line-Output Hub
The STA381BW is appropriate when a product needs digital-to-analog audio, headphone drive, and 2 Vrms line outputs in addition to powered speaker channels. By integrating these paths, it can simplify the signal chain compared with separate headphone amplifiers and line-output drivers, while retaining digital control through I2C. The FFX output stage provides efficient amplification for compatible speaker loads, and AN3959 supplies a practical 2.0-channel reference configuration. In implementation, maintain adequate output-current margin for the selected headphones, confirm the permitted load impedances in the manufacturer datasheet, and isolate unused outputs according to the reference design where necessary.
推荐
Compact Stereo Power Amplifier
The STA381BW can be used as the central amplifier in a compact stereo system when digital processing and high efficiency are more valuable than a simple analog-input amplifier. The manufacturer application note reports a 2.0-channel BTL arrangement delivering up to 2 x 20 W into 8 ohms at 18 V. That configuration can directly support two passive speakers while avoiding separate output stages and reducing inter-stage analog routing. The implementation should preserve adequate input-to-output headroom, follow the recommended decoupling and power-layout arrangement, and validate continuous thermal performance rather than relying only on the headline output-power figure.
推荐
Digital Audio Processing Platform
The STA381BW fits a digital audio platform that requires onboard signal processing, configurable control, and integrated output stages. Its I2C interface with a selectable device address supports host-controlled configuration, while the digital input path allows the source and sound processing to remain in the digital domain. This architecture can reduce analog conversion and improve system integration in connected speakers and entertainment products. Designers should review the complete register and clock requirements in the manufacturer datasheet, ensure that the selected source matches the supported audio format, and separate sensitive control routing from the high-current power-stage paths during PCB layout.
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推荐产品汇总
工程参考数据： STA381BW ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 |
|---|---|
| Product Type | 2.1-channel high-efficiency digital audio system |
| Brand | STMicroelectronics |
| Package | VQFN-48, 7 x 7 mm |
| Operating Supply Range | 26 V |
| Absolute Maximum Supply Voltage | 30 V |
| Documented Output Power | 2 x 20 W into 8 ohm at 18 V |
| Line Output | 2 Vrms |
| Headphone Output | Integrated |
| Control Interface | I2C with selectable device address |
| Power Stage | FFX power output stage |
关键差异点
- Integrated 2.1-channel signal and output path （对比 STA381BWS)
- Documented multi-channel output capability （对比 STA381BWS)
- Integrated headphone and line outputs （对比 STA381BWS)
设计说明
Use the exposed VQFN-48 thermal area as the primary heat-dissipation path and reproduce the copper arrangement shown in the STMicroelectronics documentation. At the AN3959 reference condition of 18 V and up to 2 x 20 W into 8-ohm loads, continuous output can generate substantial heat. Validate junction or board temperature in the final enclosure, especially with the power stage close to quiet signal circuits. Estimated power dissipation cannot be calculated reliably from the verified excerpts because the efficiency curve and idle-output conditions are not supplied.
Follow the manufacturer recommended layout for the VQFN-48 exposed pad, supply pins, ground connections, output routing, and digital interfaces. Keep high-current output and supply paths compact while providing adequate copper area for heat spreading, and place decoupling components directly beside their associated pins. The verified excerpts do not specify exact capacitor values or placement distances, so those details should be taken from the official STA381BW datasheet and AN3959 rather than inferred from this page.
Do not treat the 30 V absolute maximum rating as the normal operating supply, and do not assume that every channel arrangement can sustain the headline 2 x 20 W rating. The verified 20 W-per-channel figure applies to the documented 2.0-channel BTL configuration at 18 V and 8 ohms. Also verify supported digital-audio formats, I2C address selection, load restrictions, and protection requirements in the manufacturer datasheet before releasing a production PCB.
合规信息
The supplied verified excerpts do not state RoHS, REACH, lead-free, halogen-free, conflict-minerals, or AEC-Q100 status. AEC-Q100 is not applicable because this is a consumer audio IC rather than an automotive-qualified device. Consult the manufacturer product page or current material-declaration documents before making a compliance determination.
