LM4871MX/NOPB - 3W Mono Class-AB Audio Amp | Texas Instruments
部品番号: LM4871MX/NOPB ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $0.85 | $0.85 |
| 10 | $0.75 | $7.50 |
| 100 | $0.6 | $60.00 |
| 500 | $0.5 | $250.00 |
| 1,000 | $0.42 | $420.00 |
LM4871MX/NOPB 概要
An audio power amplifier is an electronic amplifier that amplifies low-power audio signals to a level suitable for driving loudspeakers. The LM4871 is a Class-AB amplifier, which offers a good compromise between efficiency and linearity, providing low distortion while consuming moderate power. In the hierarchy of audio electronics, it falls under audio amplifiers, which are a subset of analog ICs used in consumer electronics, portable devices, and multimedia systems.
Key features include a shutdown mode with low quiescent current (6.5mA typical), a wide supply voltage range of 2V to 5.5V, and a maximum output power of 3W into 3Ω. The device also offers thermal shutdown protection and is available in a lead-free (NOPB) version, compliant with RoHS. Its differential output architecture eliminates the need for output coupling capacitors, reducing external component count and board space.
The LM4871 uses a bridged-tied load (BTL) configuration, which effectively doubles the voltage swing across the load compared to a single-ended amplifier, maximizing output power without increasing supply voltage. This architecture, combined with a low-noise design, ensures clean audio reproduction. The device is designed for simplicity, requiring only a few external components, making it easy to integrate into compact designs.
Typical applications include portable speakers, mobile phones, MP3 players, and other battery-powered audio devices where high efficiency and low power consumption are critical. Its small SOIC package and minimal external component requirement make it suitable for space-constrained designs.
When designing with the LM4871, ensure proper PCB layout with adequate ground plane and decoupling capacitors close to the supply pins to minimize noise and improve thermal performance. The shutdown pin can be used for power management to extend battery life.
ドロップイン代替品: LM4871MX/NOPB — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
クイック比較ツール — 並列比較する代替部品を選択:
LM4871M/NOPB
✅ ドロップイン📋 参考代替品（カタログ未掲載）
LM4991
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
TPA2011D1
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
SSM2211SZ
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
LM4871MX/NOPB 最大定格＆電気的特性
| Output Power | 3W into 3Ω at 5V, 10% THD |
| Supply Voltage Range | 2V to 5.5V |
| 静止電流 | 6.5mA |
| Amplifier Type | Class-AB |
| Number of Channels | 1 (Mono) |
| Load Impedance | 3Ω (min) |
| THD+N | 10% (max at rated power) |
| シャットダウン電流 | 0.7µA (typical) |
| 動作温度範囲 | -40°C to 85°C |
| パッケージ | SOIC-8 (D) |
| 実装タイプ | Surface Mount |
| RoHS | Compliant |
| Lead-Free | Yes (NOPB) |
| Input Type | Analog |
| 出力タイプ | Differential |
LM4871MX/NOPB ピン構成
| ピン 1 | SHUTDOWN — Shutdown control input, active low |
| ピン 2 | BYPASS — Bypass capacitor connection |
| ピン 3 | VOUT- — Negative output |
| ピン 4 | GND — Ground |
| ピン 5 | VOUT+ — Positive output |
| ピン 6 | VDD — Power supply |
| ピン 7 | VIN- — Inverting input |
| ピン 8 | VIN+ — Non-inverting input |
主な用途
LM4871MX/NOPB の用途: 6 件s: Portable Speakers, Mobile Phones, MP3 Players, Laptop Speakers, GPS Navigation Devices, Toy and Gaming Devices.
Portable Speakers
The LM4871MX/NOPB is ideal for portable Bluetooth speakers, delivering 3W into 3Ω speakers from a 5V supply. Its low quiescent current (6.5mA) and shutdown mode (0.7µA) extend battery life. The bridged output eliminates coupling capacitors, reducing board space. With a supply range of 2V-5.5V, it works with single-cell Li-ion batteries. The SOIC-8 package is compact, and the thermal shutdown protects the device during prolonged high-power output.
おすすめ
Mobile Phones
In mobile phones, the LM4871MX/NOPB provides loudspeaker amplification for ringtones and media playback. Its 2V-5.5V supply range accommodates battery voltage variations. The shutdown mode reduces power consumption when audio is not in use, crucial for battery life. The small SOIC-8 package fits tight PCB layouts. The differential output drives the speaker directly without DC blocking capacitors, simplifying the design and improving low-frequency response.
おすすめ
MP3 Players
The LM4871MX/NOPB is well-suited for MP3 players, delivering clean audio to headphones or small speakers. Its low quiescent current (6.5mA) and shutdown mode (0.7µA) are critical for battery-powered devices. The wide supply range (2V-5.5V) ensures operation from a single Li-ion cell. The bridged output provides twice the voltage swing, maximizing output power without increasing supply voltage. The device's small footprint and minimal external components make it ideal for compact designs.
おすすめ
Laptop Speakers
The LM4871MX/NOPB can drive internal laptop speakers, providing up to 3W into 3Ω. Its 5V supply is readily available in laptops. The shutdown mode helps save power when audio is muted. The SOIC-8 package is easy to place on the motherboard. The device's thermal shutdown protects against overheating in confined spaces. The differential output reduces noise pickup, improving audio quality.
おすすめ
GPS Navigation Devices
In GPS devices, the LM4871MX/NOPB amplifies voice prompts and alerts. Its low power consumption (6.5mA quiescent) is essential for battery-operated units. The 2V-5.5V supply range matches typical battery voltages. The shutdown mode extends battery life during idle periods. The compact SOIC-8 package fits space-constrained designs. The bridged output drives small speakers efficiently, ensuring clear audio in noisy environments.
おすすめ
Toy and Gaming Devices
The LM4871MX/NOPB is used in toys and handheld gaming devices to produce sound effects and music. Its low cost and small size make it ideal for high-volume consumer products. The wide supply range (2V-5.5V) accommodates various battery configurations. The shutdown mode preserves battery life when the device is not in use. The device's robustness and thermal shutdown ensure reliable operation in demanding environments.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: LM4871MX/NOPB — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | LM4871M/NOPB | LM4991 | TPA2011D1 | SSM2211SZ |
|---|---|---|---|---|---|
| Package | SOIC-8 | SOIC-8 | SOIC-8 | SOIC-8 | SOIC-8 |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices |
| Output Power (3Ω) | 3W | 3W | 3.1W | 3.2W | 1W |
| Supply Voltage Range | 2V-5.5V | 2V-5.5V | 2V-5.5V | 2.5V-5.5V | 2.7V-5.5V |
| Quiescent Current | 6.5mA | 6.5mA | 6.5mA | 1.7mA | 4mA |
| Amplifier Class | Class-AB | Class-AB | Class-AB | Class-D | Class-AB |
| Shutdown Current | 0.7µA | 0.7µA | 0.1µA | 0.5µA | 10nA |
| Operating Temperature Range | -40°C to 85°C | -40°C to 85°C | -40°C to 85°C | -40°C to 85°C | -40°C to 85°C |
主な差別化要因
- Wide supply voltage range (2V-5.5V) （vs SSM2211SZ)
- Higher output power into 3Ω （vs SSM2211SZ)
- Lower quiescent current than TPA2011D1 （vs TPA2011D1)
設計ノート
Place a 1µF bypass capacitor close to the BYPASS pin (pin 2) and a 10µF or larger capacitor on VDD (pin 6) to ensure stability and reduce power supply noise. Use a solid ground plane to minimize ground loops and improve thermal performance. Keep input traces short and shielded to avoid noise pickup.
The LM4871MX/NOPB can dissipate significant power when driving 3Ω loads at high output. At 3W output, power dissipation is approximately 1W. The SOIC-8 package has a thermal resistance of about 100°C/W, so ensure adequate copper area on the PCB for heat sinking. For continuous high-power operation, consider adding thermal vias or a heatsink.
Do not exceed the absolute maximum supply voltage of 5.5V. Ensure the shutdown pin is not left floating; tie it to VDD for normal operation or to GND for shutdown. The differential output must not be shorted to ground or to each other. Use proper ESD protection on the input pins, as the device is sensitive to electrostatic discharge.
コンプライアンス情報
NOPB indicates lead-free and RoHS compliant. No AEC-Q100 qualification for this part.
