Overview
The L9349-LF is a monolithic IC designed by STMicroelectronics to drive inductive loads in low-side configurations, particularly suited for applications such as hydraulic valves in Anti-lock Braking Systems (ABS).
This device is engineered with extensive protection and diagnostic features to ensure reliable operation. It includes internal pull-down current sources at the enable and input pins to ensure the device is switched off in case of open input conditions. Additionally, it features output voltage slope limitation to reduce electromagnetic interference (EMI) and an integrated Zener diode clamp for fast inductive load current recirculation, limiting the output voltage to 50V during recirculation.
The L9349-LF is self-protected against short circuits at the outputs and overtemperature, with real-time error diagnosis capabilities to recognize open loads and load bypasses.
Key Specifications
| Parameter | Conditions | Value | Unit |
|---|---|---|---|
| DC Supply Voltage (VS) | -0.3 to 32 | V | |
| Supply Voltage Pulse (VSP) | -0.3 to 45 (duration < 200ms) | V | |
| Input Voltage (VIN, EN) | -1.5 to 6 | V | |
| DC Output Current (IO1, 2) | 5 A (typ.) | A | |
| DC Output Current (IO3, 4) | 3 A (typ.) | A | |
| Junction Temperature (Tj1) | -40 to 150 | °C | |
| Package | PowerSO-20 |
Key Features
- Electrostatic discharge (ESD) protection
- Selective overtemperature shutdown
- Overload disable
- Load bypass detection
- Four low-side output drivers with protection diagnostics:
- 2 channels with 5 A output current capability and rON = 0.2 Ω (typ.)
- 2 channels with 3 A output current capability and rON = 0.3 Ω (typ.)
- Output slope control
- Integrated 60 V Zener diodes output clamping structure
- Open load detection in ON and OFF conditions
- Signal and power ground loss shutdown
- Short circuit protection
Applications
The L9349-LF is primarily designed for automotive applications, particularly for driving inductive loads such as hydraulic valves in Anti-lock Braking Systems (ABS). It is also suitable for other applications requiring robust and reliable low-side switching with extensive diagnostic capabilities.
Q & A
- What is the primary application of the L9349-LF?
The L9349-LF is primarily used in automotive applications, such as driving hydraulic valves in Anti-lock Braking Systems (ABS).
- What type of protection does the L9349-LF offer against failures?
The device offers protection against short circuits, overtemperature, and electromagnetic interference (EMI). It also includes ESD protection and load bypass detection.
- How many output channels does the L9349-LF have?
The L9349-LF has four low-side output driver channels, with two channels capable of 5 A output current and two channels capable of 3 A output current.
- What is the operating temperature range of the L9349-LF?
The operating temperature range is from -40°C to 150°C.
- What package type is the L9349-LF available in?
The L9349-LF is available in the PowerSO-20 package.
- How does the L9349-LF handle open load conditions?
The device can detect open loads in both ON and OFF conditions and provides diagnostic outputs to indicate these conditions.
- What is the purpose of the integrated Zener diode clamp in the L9349-LF?
The integrated Zener diode clamp is used for fast inductive load current recirculation, limiting the output voltage to 50V during the recirculation phase.
- How does the L9349-LF protect against power and signal ground loss?
The device includes features for signal and power ground loss shutdown to ensure safe operation.
- What is the diagnostic delay time for overload conditions in the L9349-LF?
The diagnostic overload delay switch-off time is between 6 to 65 microseconds for supply voltages between 9V and 16V.
- Can the L9349-LF detect load bypasses?
Yes, the device can detect load bypasses by comparing the output voltages with a fixed offset in the OFF condition).
