L9758 - Automotive Dual Voltage Regulator | STMicroelectronics
MPN： L9758 ✓ 啟用中L9758 概覽
A voltage regulator is an electronic circuit that maintains a constant output voltage regardless of changes in input voltage or load current. Linear regulators, such as LDOs, achieve this by dissipating excess power as heat, providing low output noise and fast transient response. The L9758 belongs to the category of power management ICs, which are essential for converting raw battery voltage into clean, regulated rails for sensitive electronics. In automotive systems, voltage regulators are critical for ensuring reliable operation of ECUs, sensors, and communication modules.
Key features of the L9758 include two independent LDO outputs with output voltages of 5V and 3.3V, each capable of delivering up to 400mA of load current. The device features a low dropout voltage of 0.5V at full load, enabling efficient operation even when the input voltage is close to the output. It also includes overcurrent and thermal shutdown protection, ensuring robust performance in harsh automotive environments. The L9758 is AEC-Q100 qualified, meeting the stringent reliability requirements for automotive applications.
The L9758 utilizes a bipolar process technology, providing stable and accurate output voltages with a tolerance of ±2%. The device includes an internal bandgap reference, which ensures consistent performance over temperature. The PowerSO-20 package features an exposed pad for enhanced thermal dissipation, allowing the device to handle power dissipation up to 2W without external heatsinking. The L9758 also includes an enable pin for each regulator, enabling power sequencing in multi-rail systems.
Typical applications for the L9758 include engine control units (ECUs), transmission control modules, body control modules, and sensor power supplies. In an ECU, the L9758 provides clean 5V and 3.3V rails for the microcontroller and peripheral sensors, ensuring stable operation under varying load conditions. The device's wide input voltage range and automotive qualification make it ideal for use in 12V and 24V vehicle electrical systems.
When designing with the L9758, it is important to ensure adequate input and output capacitance to maintain stability. A 10uF ceramic capacitor on the input and a 10uF ceramic capacitor on each output are recommended. The exposed pad should be soldered to a large copper area on the PCB to enhance thermal performance. Additionally, the enable pins can be used to implement power sequencing, which is critical for preventing latch-up in mixed-voltage systems.
直接替換替代品，適用於 L9758 — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
L9758TR
✅ 直接替換📋 參考替代品（不在目錄中）
TLE4267
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MC33269
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
L9758 最大額定值與電氣特性
| 輸出數量 | 2 |
| Output Voltage 1 | 5 V |
| Output Voltage 2 | 3.3 V |
| Output Current per Channel | 400 mA |
| 輸入電壓範圍 | 5.5 V to 18 V |
| 壓降電壓 | 0.5 V at 400 mA |
| Output Voltage Tolerance | ±2% |
| 靜態電流 | 80 uA |
| Line Regulation | 10 mV |
| Load Regulation | 20 mV |
| 工作溫度範圍 | -40C to +125C |
| 封裝 | PowerSO-20 |
| 安裝類型 | Surface Mount |
| AEC-Q100 Qualified | Yes |
| RoHS Compliant | Yes |
| 致能腳位 | Yes (2 pins) |
| 過熱關機 | Yes |
| 過電流保護 | Yes |
L9758 腳位配置
| 腳位 1 | EN1 — Enable for regulator 1 (active high) |
| 腳位 2 | IN1 — Input supply for regulator 1 |
| 腳位 3 | GND — Ground |
| 腳位 4 | OUT1 — Output of regulator 1 (5V) |
| 腳位 5 | NC — No connect |
| 腳位 6 | NC — No connect |
| 腳位 7 | OUT2 — Output of regulator 2 (3.3V) |
| 腳位 8 | GND — Ground |
| 腳位 9 | IN2 — Input supply for regulator 2 |
| 腳位 10 | EN2 — Enable for regulator 2 (active high) |
| 腳位 11 | NC — No connect |
| 腳位 12 | NC — No connect |
| 腳位 13 | NC — No connect |
| 腳位 14 | NC — No connect |
| 腳位 15 | NC — No connect |
| 腳位 16 | NC — No connect |
| 腳位 17 | NC — No connect |
| 腳位 18 | NC — No connect |
| 腳位 19 | NC — No connect |
| 腳位 20 | NC — No connect |
| 腳位 21 | PAD — Exposed pad (thermal and ground) |
典型應用
L9758 適用於 6 應用s: Engine Control Unit (ECU), Transmission Control Module, Body Control Module, Sensor Power Supply, Infotainment System, Advanced Driver Assistance Systems (ADAS).
Engine Control Unit (ECU)
The L9758 provides clean 5V and 3.3V rails for the microcontroller and sensors in an ECU. Its wide input voltage range (5.5V to 18V) handles battery voltage variations during cranking, while the low dropout voltage ensures stable operation even when the battery voltage dips. The AEC-Q100 qualification guarantees reliability in harsh automotive environments. In a typical ECU, the L9758 is placed after the main power supply, with 10uF capacitors on input and outputs to ensure stability. The enable pins allow power sequencing to prevent latch-up in mixed-voltage systems. Compared to discrete regulators, the L9758 reduces component count and PCB area, improving overall system reliability.
推薦
Transmission Control Module
In transmission control modules, the L9758 supplies regulated power to the transmission control unit and its sensors. The dual outputs provide separate rails for digital and analog circuits, reducing noise coupling. The overcurrent and thermal shutdown protection safeguard the module against faults. The PowerSO-20 package with exposed pad allows efficient heat dissipation, essential for under-hood applications. The L9758's low quiescent current helps minimize battery drain when the vehicle is off. In a typical design, the L9758 is powered from the ignition switch, with the enable pins controlled by the main microcontroller for sequenced startup.
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Body Control Module
The L9758 is used in body control modules to power the central microcontroller and peripheral interfaces. Its 5V output can power logic circuits, while the 3.3V output is suitable for low-voltage sensors and communication interfaces. The wide input range accommodates load dump transients, and the AEC-Q100 qualification ensures long-term reliability. The device's small footprint and integrated protection features simplify PCB design. In a body control module, the L9758 is often placed near the battery input, with reverse battery protection diodes and input filtering capacitors. The enable pins can be used to implement sleep modes, reducing power consumption when the vehicle is parked.
推薦
Sensor Power Supply
The L9758 provides stable power to various automotive sensors, such as pressure, temperature, and position sensors. The low output noise and tight regulation (±2%) ensure accurate sensor readings. The dual outputs allow powering multiple sensors with different voltage requirements. The device's thermal shutdown and overcurrent protection prevent damage from sensor faults. In a sensor module, the L9758 is typically powered from the vehicle's 12V rail, with a 10uF capacitor on the input and 1uF capacitors on the outputs. The enable pins can be used to power down sensors when not in use, saving energy.
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Infotainment System
In infotainment systems, the L9758 provides clean power for the main processor and audio codec. The 5V rail can power the processor's I/O, while the 3.3V rail powers the memory and logic. The low dropout voltage ensures stable operation even when the battery voltage drops during audio playback. The device's low noise output is critical for audio quality. The L9758 is typically placed after a buck converter, with additional filtering capacitors to minimize ripple. The enable pins allow the system to enter low-power standby mode when the ignition is off.
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Advanced Driver Assistance Systems (ADAS)
The L9758 is used in ADAS modules to power the vision processor and sensor interface. The dual outputs provide separate rails for digital and analog circuits, reducing interference. The wide input voltage range handles voltage transients from the vehicle's electrical system. The AEC-Q100 qualification ensures reliability in safety-critical applications. In an ADAS module, the L9758 is often powered from a protected battery line, with input filtering and reverse protection. The enable pins can be used to implement fail-safe power sequencing, ensuring the processor starts up correctly.
推薦
推薦產品摘要
工程參考資料，適用於 L9758 — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | L9758TR | TLE4267 | MC33269 |
|---|---|---|---|---|
| Package | PowerSO-20 | PowerSO-20 | PowerSO-20 | PowerSO-20 |
| Brand | STMicroelectronics | STMicroelectronics | Infineon | onsemi |
| Output Voltage 1 | 5V | 5V | 5V | 5V |
| Output Voltage 2 | 3.3V | 3.3V | 3.3V | 3.3V |
| Output Current per Channel | 400mA | 400mA | 400mA | 500mA |
| Input Voltage Range | 5.5V to 18V | 5.5V to 18V | 5.5V to 18V | 5.5V to 18V |
| Dropout Voltage | 0.5V | 0.5V | 0.5V | 0.5V |
| AEC-Q100 Qualified | Yes | Yes | Yes | Yes |
主要差異化特點
- Dual LDO with 5V and 3.3V outputs in one package (對比TLE4267)
- AEC-Q100 qualified for automotive (對比MC33269)
- Low quiescent current of 80uA per regulator (對比TLE4267)
設計說明
The L9758 in PowerSO-20 package has a thermal resistance of 40C/W (theta_JA). At maximum load (400mA on each output) with 12V input and 5V/3.3V outputs, power dissipation is approximately 2.6W, resulting in a junction temperature rise of 104C. Ensure adequate copper area on the PCB and consider a heatsink or forced airflow for high ambient temperatures.
Place input and output capacitors as close to the pins as possible. Use 10uF ceramic capacitors on each input and output. Add a 0.1uF ceramic capacitor in parallel for high-frequency decoupling. The exposed pad should be soldered to a large ground plane to improve thermal performance.
Do not exceed the maximum input voltage of 18V. Ensure the enable pins are properly driven; floating enable pins may cause unpredictable behavior. Use pull-down resistors on the enable pins if they are not driven by a microcontroller. Also, verify that the output capacitors have sufficient ESR to maintain stability.
合規資訊
RoHS compliant and AEC-Q100 qualified per STMicroelectronics product page. Halogen-free status not specified in available data.
