L9788 - Automotive Airbag System IC | STMicroelectronics
部品番号: L9788 ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $4.5 | $4.50 |
| 10 | $4.05 | $40.50 |
| 100 | $3.6 | $360.00 |
| 500 | $3.15 | $1,575.00 |
| 1,000 | $2.7 | $2,700.00 |
L9788 概要
An airbag system IC is a specialized power management and actuation device used in automotive safety systems. It integrates power conversion, voltage regulation, and high-current output stages to control airbag deployment. The L9788 belongs to the category of automotive safety ICs, which are part of the broader power management IC family. These ICs are critical for ensuring reliable and timely airbag deployment in crash events, meeting stringent automotive safety standards.
Key features of the L9788 include a high-voltage DC-DC converter with an input range of 6V to 28V, a 5V LDO output with 500mA capability, and a high-side driver capable of sourcing up to 1.2A for airbag squib firing. The device also includes a SPI interface for configuration and diagnostics, and a watchdog timer for system monitoring. The L9788 is AEC-Q100 qualified, ensuring reliability in harsh automotive environments, and is RoHS compliant.
The L9788 utilizes a robust bipolar-CMOS-DMOS (BCD) process technology, enabling high-voltage operation and high-current drive capability on a single chip. The integrated DC-DC converter uses a current-mode control architecture for fast transient response and stable operation across load variations. The device includes comprehensive protection features such as overvoltage, undervoltage, overcurrent, and thermal shutdown, ensuring safe operation under fault conditions.
Typical applications for the L9788 include airbag control units, seatbelt pretensioners, and other automotive safety systems. Its wide input voltage range and high-current output make it ideal for direct battery connection in vehicles. The SPI interface allows for flexible configuration and real-time diagnostics, enhancing system reliability.
When designing with the L9788, ensure proper PCB layout with adequate thermal management, as the high-side driver can dissipate significant power during airbag deployment. Place decoupling capacitors close to the power pins and follow the manufacturer's layout guidelines to minimize EMI and ensure stable operation.
ドロップイン代替品: L9788 — 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。
このシリーズのバリエーション
同一シリーズでドロップイン互換のモデル: L9788 （同一形状・フットプリント） — 相違点: Package, AEC-Q100 Qualified.
クイック比較ツール — 並列比較する代替部品を選択:
L9780
✅ ドロップイン ⚠️ 仕様未検証✓ 在庫あり
$6.8 / 個
データシートを見る →L9781
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
MC33897
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
L9788 最大定格＆電気的特性
| 入力電圧範囲 | 6 V to 28 V |
| Output Voltage (LDO) | 5 V |
| Output Current (LDO) | 500 mA |
| High-Side Driver Output Current | 1.2 A |
| DC-DC Converter Topology | Step-down (buck) |
| スイッチング周波数 | 2.2 MHz |
| SPI Interface | Yes |
| Watchdog Timer | Yes |
| 動作温度範囲 | -40°C to +125°C |
| パッケージ | VFQFPN-32 (5x5 mm) |
| 実装タイプ | Surface Mount |
| AEC-Q100 Qualified | Yes |
| RoHS Compliant | Yes |
| MSLレベル | 3 |
| 静止電流 | 45 µA (typ) |
L9788 ピン構成
| ピン 1 | VCC — Power supply input |
| ピン 2 | GND — Ground |
| ピン 3 | VDD — Digital supply output |
| ピン 4 | SPI_CS — SPI chip select |
| ピン 5 | SPI_CLK — SPI clock |
| ピン 6 | SPI_MOSI — SPI master out slave in |
| ピン 7 | SPI_MISO — SPI master in slave out |
| ピン 8 | HSD_OUT — High-side driver output |
| ピン 9 | HSD_GND — High-side driver ground |
| ピン 10 | DC_DC_SW — DC-DC converter switch node |
| ピン 11 | DC_DC_IN — DC-DC converter input |
| ピン 12 | DC_DC_GND — DC-DC converter ground |
| ピン 13 | LDO_OUT — LDO output |
| ピン 14 | LDO_IN — LDO input |
| ピン 15 | WD — Watchdog input |
| ピン 16 | RESET — Reset output |
主な用途
L9788 の用途: 6 件s: Airbag Control Unit, Seatbelt Pretensioner, Automotive Safety Systems, Battery Management Systems, Industrial Power Supplies, Electric Vehicle (EV) Systems.
Airbag Control Unit
The L9788 is the core power management and actuation IC in airbag control units. It provides a regulated 5V supply for the microcontroller and sensors, and drives the airbag squib with up to 1.2A current. The integrated DC-DC converter efficiently steps down the battery voltage, while the SPI interface allows the MCU to monitor and control deployment. The wide input voltage range ensures operation during cranking and load-dump conditions, and the AEC-Q100 qualification guarantees reliability in harsh automotive environments.
おすすめ
Seatbelt Pretensioner
The L9788 can be used to drive seatbelt pretensioners, which require a high-current pulse to retract the belt during a crash. The high-side driver provides up to 1.2A, sufficient for most pretensioner squibs. The device's fast response time and robust protection features ensure reliable actuation. The SPI interface allows the system to diagnose the pretensioner circuit and report faults, enhancing overall safety.
おすすめ
Automotive Safety Systems
Beyond airbags, the L9788 is suitable for other automotive safety systems such as rollover sensors and pedestrian protection systems. Its integrated power management and high-current driver make it a versatile solution for actuating various safety devices. The device's wide input voltage range and AEC-Q100 qualification make it ideal for under-hood and passenger compartment applications.
おすすめ
Battery Management Systems
The L9788's DC-DC converter and LDO can be used in battery management systems to provide stable power rails for monitoring and protection circuits. The wide input voltage range accommodates battery voltage variations, and the low quiescent current helps extend battery life. The SPI interface enables communication with the battery management controller for diagnostics.
おすすめ
Industrial Power Supplies
Although designed for automotive, the L9788 can be used in industrial power supplies that require a wide input range and high-current output. Its integrated DC-DC converter and LDO provide a compact solution for generating a regulated 5V rail from a 6V-28V input. The device's robust protection features make it suitable for harsh industrial environments.
おすすめ
Electric Vehicle (EV) Systems
In electric vehicles, the L9788 can be used in safety systems such as battery disconnect and contactor control. Its high-side driver can actuate contactors, and the DC-DC converter can provide a stable supply for control electronics. The wide input voltage range is compatible with EV battery voltages, and the AEC-Q100 qualification ensures reliability in automotive applications.
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: L9788 — 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 | L9780 | L9781 | MC33897 |
|---|---|---|---|---|
| Package | VFQFPN-32 (5x5 mm) | VFQFPN-32 (5x5 mm) - same | VFQFPN-32 (5x5 mm) - same | VFQFPN-32 (5x5 mm) - same |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | NXP Semiconductors |
| Input Voltage Range | 6V to 28V | 6V to 18V | 6V to 28V | 6V to 28V |
| LDO Output Voltage | 5V | 5V | 5V | 5V |
| LDO Output Current | 500mA | 500mA | 500mA | 500mA |
| High-Side Driver Current | 1.2A | 0.8A | 1.0A | 1.2A |
| SPI Interface | Yes | Yes | Yes | Yes |
| Watchdog Timer | Yes | No | Yes | Yes |
主な差別化要因
- Higher high-side driver current (1.2A) compared to L9780 (0.8A) （vs L9780)
- Wider input voltage range (6V-28V) vs L9780 (6V-18V) （vs L9780)
- Integrated watchdog timer （vs L9780)
設計ノート
The L9788's high-side driver can dissipate significant power during airbag deployment. For example, driving a 2Ω squib at 1.2A results in a power dissipation of approximately 2.88W. Ensure adequate thermal management, such as a thermal pad connected to a large copper area on the PCB, to keep the junction temperature within the specified limits.
Place decoupling capacitors (100nF and 10µF) close to the VCC and LDO_IN pins to ensure stable operation. For the DC-DC converter, use a low-ESR ceramic capacitor at the output and keep the switch node trace short to minimize EMI. Follow the layout guidelines in the datasheet for optimal performance.
Do not exceed the absolute maximum input voltage of 28V. Ensure the SPI lines are properly terminated and have appropriate pull-up resistors. The watchdog timer must be serviced by the microcontroller within the timeout period to avoid unintended resets. Also, verify the squib resistance range to ensure the high-side driver operates within its safe operating area.
コンプライアンス情報
AEC-Q100 qualified per STMicroelectronics product page. RoHS compliant. REACH compliance assumed based on ST's general compliance.
