L9951 - Automotive Door Actuator Driver | STMicroelectronics
MPN: L9951 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.2 | $4.20 |
| 10 | $3.8 | $38.00 |
| 100 | $3.4 | $340.00 |
| 500 | $3.1 | $1,550.00 |
| 1,000 | $2.8 | $2,800.00 |
Drop-in alternatives for L9951 β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
L9950
β Drop-Inπ Reference alternative (not in catalog)
VNH5019A
β Drop-Inπ Reference alternative (not in catalog)
BTN8982TA
β Drop-Inπ Reference alternative (not in catalog)
L9951 Maximum Ratings & Electrical Characteristics
| Supply Voltage Range | 4.5 V to 28 V |
| Peak Output Current | 5.2 A |
| Continuous Output Current | 3.5 A |
| Output Configuration | Full H-bridge |
| Standby Quiescent Current | 50 Β΅A |
| Operating Temperature Range | -40Β°C to +150Β°C |
| Package | PowerSO-20 |
| Mounting Type | Surface Mount |
| Interface | SPI |
| Protection Features | Overcurrent, Overtemperature, Short-circuit |
| Diagnostics | SPI fault reporting |
| RoHS Status | Compliant |
| AEC-Q100 Qualified | Yes |
| Thermal Resistance (junction-to-ambient) | 35 Β°C/W |
| Output Voltage Drop | 1.5 V at 3.5 A |
L9951 Pin Configuration
| Pin 1 | VS β Battery supply voltage |
| Pin 2 | OUT1 β H-bridge output 1 |
| Pin 3 | OUT2 β H-bridge output 2 |
| Pin 4 | GND β Ground |
| Pin 5 | GND β Ground |
| Pin 6 | CSN β SPI chip select (active low) |
| Pin 7 | SCK β SPI clock |
| Pin 8 | SDI β SPI data input |
| Pin 9 | SDO β SPI data output |
| Pin 10 | EN β Enable input |
| Pin 11 | IN1 β Control input 1 |
| Pin 12 | IN2 β Control input 2 |
| Pin 13 | GND β Ground |
| Pin 14 | GND β Ground |
| Pin 15 | VS β Battery supply voltage |
| Pin 16 | VS β Battery supply voltage |
| Pin 17 | OUT2 β H-bridge output 2 |
| Pin 18 | OUT1 β H-bridge output 1 |
| Pin 19 | GND β Ground |
| Pin 20 | GND β Ground |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
L9951 is suitable for 6 applications: Central Locking System, Mirror Adjustment, Seat Adjustment, Window Lift, Tailgate Actuator, Fuel Flap Actuator.
Central Locking System
The L9951 drives the door lock actuator motor in central locking systems. Its 5.2 A peak current capability ensures reliable locking/unlocking even under mechanical load. The SPI interface allows the body control module to monitor lock status and detect faults, enhancing security and diagnostics. The wide supply voltage range (4.5 V to 28 V) accommodates battery voltage variations during cranking and load dump. The H-bridge configuration enables bidirectional motor control for lock and unlock operations. Thermal protection prevents damage during prolonged activation, ensuring long-term reliability.
Recommended
Mirror Adjustment
The L9951 controls the DC motors that adjust side mirrors. Its low quiescent current (50 Β΅A) minimizes battery drain when the vehicle is off, which is critical for standby power budgets. The SPI diagnostics allow the BCM to detect mirror position faults and report them to the driver. The device's overcurrent protection prevents damage if the mirror is manually forced, and the overtemperature protection ensures safe operation in hot climates. The compact PowerSO-20 package fits into tight mirror housings, and the wide temperature range (-40Β°C to +150Β°C) ensures operation in extreme conditions.
Recommended
Seat Adjustment
The L9951 drives the motors for seat position adjustment, providing up to 5.2 A peak current to handle the high torque required for moving seats. The H-bridge allows bidirectional control for forward/backward and up/down movements. The SPI interface enables precise control and diagnostics, allowing the BCM to store seat positions and detect obstructions. The device's robust protection features ensure safe operation in case of a jammed seat, and the wide supply voltage range handles voltage transients during motor start. The PowerSO-20 package with exposed pad ensures efficient heat dissipation during continuous operation.
Recommended
Window Lift
The L9951 is suitable for window lift motors, providing up to 5.2 A peak current to overcome window seal friction. Its SPI diagnostics allow the BCM to detect window position and anti-pinch events, enhancing safety. The device's overcurrent protection prevents motor damage if the window is obstructed, and the overtemperature protection ensures reliable operation during repeated use. The wide supply voltage range (4.5 V to 28 V) ensures operation during engine start, and the low standby current minimizes battery drain when the vehicle is off. The H-bridge configuration enables smooth up/down control.
Recommended
Tailgate Actuator
The L9951 drives the tailgate actuator motor, providing high current for lifting heavy tailgates. Its 5.2 A peak current capability ensures reliable operation even under load. The SPI interface allows the BCM to monitor tailgate position and detect faults, improving convenience and safety. The device's protection features prevent damage from overcurrent or overtemperature, and the wide supply voltage range accommodates battery voltage variations. The PowerSO-20 package is suitable for mounting in the tailgate module, and the AEC-Q100 qualification ensures reliability in automotive environments.
Recommended
Fuel Flap Actuator
The L9951 controls the fuel flap actuator motor, providing precise and reliable operation. Its low quiescent current (50 Β΅A) is ideal for applications that remain in standby for long periods. The SPI diagnostics allow the BCM to detect flap position and faults, enhancing security. The device's overcurrent protection prevents damage if the flap is forced, and the overtemperature protection ensures safe operation. The compact PowerSO-20 package fits into tight spaces, and the wide temperature range (-40Β°C to +150Β°C) ensures operation in all climates.
Recommended
Recommended Products Summary
Engineering reference data for L9951 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | L9950 | VNH5019A | BTN8982TA |
|---|---|---|---|---|
| Package | PowerSO-20 | PowerSO-20 | PowerSO-20 | PowerSO-20 |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | Infineon |
| Peak Output Current | 5.2 A | 3.5 A | 30 A | 15 A |
| Supply Voltage Range | 4.5 V to 28 V | 4.5 V to 18 V | 5.5 V to 18 V | 6 V to 18 V |
| Interface | SPI | SPI | PWM | PWM |
| Standby Quiescent Current | 50 Β΅A | 50 Β΅A | 5 Β΅A | 7 Β΅A |
| AEC-Q100 Qualified | Yes | Yes | Yes | Yes |
| Protection Features | Overcurrent, Overtemperature, Short-circuit | Overcurrent, Overtemperature | Overcurrent, Overtemperature, Short-circuit | Overcurrent, Overtemperature, Short-circuit |
Key Differentiators
- Higher peak current than L9950 (vs L9950)
- Wider supply voltage range (vs L9950)
- SPI diagnostics (vs VNH5019A)
Design Notes
The L9951 in PowerSO-20 package has a thermal resistance of 35 Β°C/W (junction-to-ambient). At 3.5 A continuous current with a 1.5 V drop, power dissipation is 5.25 W, causing a temperature rise of 184 Β°C. Ensure adequate PCB copper area and thermal vias to keep the junction temperature below 150 Β°C. For high-current applications, consider a heatsink or forced air cooling.
Place a 100 nF ceramic capacitor and a 10 Β΅F electrolytic capacitor close to the VS pins to handle inrush currents during motor start. Use a solid ground plane and connect the exposed pad to it with multiple vias to improve thermal performance. Keep SPI signal traces short and shielded to avoid noise coupling.
Do not exceed the absolute maximum supply voltage of 28 V, as this can damage the device. Ensure the motor's back-EMF is clamped with external flyback diodes if the motor is not internally protected. The SPI interface requires proper pull-up resistors on CSN and SCK lines to avoid floating inputs during power-up.
Compliance Information
RoHS compliant and AEC-Q100 qualified per STMicroelectronics product page.
