Overview
The L9911U is a multifunction smart voltage regulator designed by STMicroelectronics, specifically tailored for automotive applications. This component is part of STMicroelectronics' range of power management ICs and is particularly suited for car alternator voltage regulation. It offers a robust set of features to ensure reliable and efficient voltage regulation in various automotive systems.
Key Specifications
| Parameter | Value |
|---|---|
| Manufacturer | STMicroelectronics |
| Input Voltage Range | 7 V to 18 V |
| Output Voltage Range | 14.4 ± 0.4 V @ 20°C |
| Starting Speed | 1320 rpm @ RT |
| LRC Cut-off Speed | 3000 ± 300 rpm @ RT |
| LRC Duty Cycle/Starting Duty Cycle | 2.5/2 seconds |
| Field Driver | High Side (HS) -3.5 ± 1 |
| Operating Temperature Range | -40°C to 150°C |
| Package | Multiwatt8 |
Key Features
- High Accuracy Voltage Regulation: The L9911U provides a precise output voltage of 14.4 ± 0.4 V at 20°C, ensuring stable voltage supply to automotive systems.
- Robust Protection Features: Includes short circuit protection from -5 V to 36 V, slope control to reduce EMI and RFI, and high ESD level up to 4 kV.
- High Speed Mode: Operates in high speed mode (<1 MHz) and low speed mode (<250 kHz).
- Lamp and Relay Drivers: Supports lamp and relay drivers with specific duty cycles and cut-off speeds.
- Thermal and Overload Protection: Features over-temperature, over-load, and short-to-ground protections.
Applications
The L9911U is primarily used in automotive systems for car alternator voltage regulation. It is suitable for various applications including:
- Automotive powertrain systems.
- Alternator voltage regulation.
- Lamp and relay control in vehicles.
- General automotive electronics requiring precise voltage regulation.
Q & A
- What is the primary function of the L9911U?
The primary function of the L9911U is to act as a multifunction smart voltage regulator for car alternators in automotive systems. - What is the input voltage range of the L9911U?
The input voltage range of the L9911U is 7 V to 18 V. - What is the output voltage of the L9911U?
The output voltage of the L9911U is 14.4 ± 0.4 V at 20°C. - What are the starting and LRC cut-off speeds of the L9911U?
The starting speed is 1320 rpm @ RT, and the LRC cut-off speed is 3000 ± 300 rpm @ RT. - What protection features does the L9911U offer?
The L9911U offers short circuit protection, slope control to reduce EMI and RFI, high ESD level up to 4 kV, and thermal and overload protections. - What is the operating temperature range of the L9911U?
The operating temperature range of the L9911U is -40°C to 150°C. - What package type is the L9911U available in?
The L9911U is available in the Multiwatt8 package. - Is the L9911U suitable for high-speed applications?
Yes, the L9911U operates in high speed mode (<1 MHz) and low speed mode (<250 kHz). - Does the L9911U support lamp and relay drivers?
Yes, the L9911U supports lamp and relay drivers with specific duty cycles and cut-off speeds. - What are some common applications of the L9911U?
The L9911U is commonly used in automotive powertrain systems, alternator voltage regulation, and lamp and relay control in vehicles.
