L9971 - Automotive Dual H-Bridge Driver | STMicroelectronics
MPN: L9971 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.5 | $4.50 |
| 10 | $4.05 | $40.50 |
| 100 | $3.6 | $360.00 |
| 500 | $3.24 | $1,620.00 |
| 1,000 | $2.88 | $2,880.00 |
Drop-in alternatives for L9971 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:
L9958
β Drop-Inβ 99,999 In Stock
$2.7 / Unit
View Datasheet βDRV8876
β Drop-Inπ Reference alternative (not in catalog)
VNH5019
β Drop-Inπ Reference alternative (not in catalog)
L9971 Maximum Ratings & Electrical Characteristics
| Supply Voltage Range | 5.5 V to 36 V |
| Output Current (per channel) | 1.2 A (DC) |
| Number of H-Bridges | 2 |
| Control Interface | SPI |
| Standby Current | 10 uA (typ) |
| Operating Temperature Range | -40Β°C to +150Β°C |
| Package | PowerSO-20 |
| Mounting Type | Surface Mount |
| Protection Features | Overcurrent, Overtemperature, Short-Circuit |
| Diagnostic Features | SPI fault reporting |
| AEC-Q100 Qualification | Yes |
| RoHS Status | Compliant |
| Output Type | Dual H-Bridge |
| Switching Frequency | [DATA_NEEDED: Switching frequency] |
| Thermal Resistance (junction-to-ambient) | [DATA_NEEDED: Thermal resistance] |
L9971 Pin Configuration
| Pin 1 | OUT1 β H-Bridge 1 output |
| Pin 2 | OUT2 β H-Bridge 1 output |
| Pin 3 | GND β Ground |
| Pin 4 | VS β Supply voltage |
| Pin 5 | OUT3 β H-Bridge 2 output |
| Pin 6 | OUT4 β H-Bridge 2 output |
| Pin 7 | GND β Ground |
| Pin 8 | VS β Supply voltage |
| Pin 9 | SCK β SPI clock |
| Pin 10 | SDI β SPI data input |
| Pin 11 | SDO β SPI data output |
| Pin 12 | CS β SPI chip select |
| Pin 13 | EN β Enable |
| Pin 14 | DIAG β Diagnostic output |
| Pin 15 | GND β Ground |
| Pin 16 | VS β Supply voltage |
| Pin 17 | OUT5 β H-Bridge 2 output |
| Pin 18 | OUT6 β H-Bridge 2 output |
| Pin 19 | GND β Ground |
| Pin 20 | VS β Supply voltage |
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
L9971 is suitable for 6 applications: Automotive Power Windows, Sunroof Control, Seat Adjustment, Industrial Automation, Robotics, Medical Equipment.
Automotive Power Windows
The L9971 drives the DC motor for power windows, providing bidirectional control and protection. Its 1.2A output current is sufficient for window lift motors, and the SPI interface allows precise control and diagnostics. The wide supply voltage range (5.5V to 36V) accommodates automotive battery voltage variations. The low standby current (10 uA) minimizes battery drain when the window is not in use. The AEC-Q100 qualification ensures reliable operation in the harsh automotive environment, with overcurrent and overtemperature protection preventing damage during jamming or overload conditions.
Recommended
Sunroof Control
The L9971 is used to control the sunroof motor, providing forward and reverse operation. Its dual H-bridge configuration allows independent control of two motors if needed. The SPI interface enables the microcontroller to monitor motor current and detect obstacles, enhancing safety. The device's thermal protection ensures reliable operation even during prolonged use. The PowerSO-20 package with exposed pad aids in heat dissipation, making it suitable for the confined space of a sunroof module.
Recommended
Seat Adjustment
The L9971 drives the seat adjustment motors for forward/backward and recline functions. Its 1.2A output current is adequate for small seat motors. The SPI interface allows the system to read fault status and adjust motor speed via PWM. The wide operating temperature range (-40Β°C to +150Β°C) ensures operation in extreme climates. The device's short-circuit protection prevents damage to the motor and wiring in case of a fault.
Recommended
Industrial Automation
In industrial automation, the L9971 can be used to control small DC motors in conveyor belts, actuators, and robotic arms. Its robust protection features and SPI diagnostics make it suitable for industrial environments. The wide supply voltage range allows operation from 24V industrial supplies. The device's low standby current is beneficial for energy-efficient systems. The PowerSO-20 package is easy to solder and provides good thermal performance.
Recommended
Robotics
The L9971 is used in robotics for driving DC motors in wheels, arms, and grippers. Its dual H-bridge allows control of two motors independently, enabling differential drive. The SPI interface provides real-time diagnostics, which is crucial for autonomous systems. The device's overcurrent protection prevents motor burnout in stall conditions. The compact PowerSO-20 package is ideal for space-constrained robot designs.
Recommended
Medical Equipment
The L9971 can be used in medical equipment such as hospital beds, infusion pumps, and diagnostic devices that require precise motor control. Its low standby current and high reliability make it suitable for battery-powered medical devices. The SPI interface allows for accurate speed and position control. The device's protection features ensure safe operation in critical applications. The AEC-Q100 qualification, while automotive-focused, also indicates high reliability suitable for medical use.
Recommended
Recommended Products Summary
Engineering reference data for L9971 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | L9958 | DRV8876 | VNH5019 |
|---|---|---|---|---|
| Package | PowerSO-20 | PowerSO-20 | PowerSO-20 | PowerSO-20 |
| Brand | STMicroelectronics | STMicroelectronics | Texas Instruments | STMicroelectronics |
| Output Current (per channel) | 1.2 A | 8.5 A | 3.5 A | 30 A |
| Supply Voltage Range | 5.5V to 36V | 5.5V to 36V | 4.5V to 36V | 5.5V to 36V |
| Control Interface | SPI | SPI | PWM | PWM |
| Standby Current | 10 uA | 5 uA | 1 uA | 5 uA |
| AEC-Q100 Qualified | Yes | Yes | No | Yes |
| Protection Features | Overcurrent, Overtemperature, Short-Circuit | Overcurrent, Overtemperature, Short-Circuit | Overcurrent, Overtemperature, Short-Circuit | Overcurrent, Overtemperature, Short-Circuit |
Key Differentiators
- SPI control and diagnostics (vs DRV8876)
- AEC-Q100 qualification (vs DRV8876)
- Lower output current for cost optimization (vs L9958)
Design Notes
The PowerSO-20 package has an exposed pad that must be soldered to a large copper area on the PCB to ensure adequate heat dissipation. For continuous operation at 1.2A per channel, calculate the power dissipation and ensure the junction temperature stays below 150Β°C. Use thermal vias to improve heat transfer to the ground plane.
Place 100nF and 10uF decoupling capacitors close to the VS pins to suppress voltage spikes during motor switching. Use a star-ground topology to minimize ground bounce. Keep the SPI lines short and shielded to avoid noise coupling from the motor currents.
Do not exceed the absolute maximum supply voltage of 40V. Ensure the motor's back-EMF is clamped with external flyback diodes if the motor is not internally protected. The SPI interface must be configured correctly to avoid unintended motor activation. Always enable the device after proper initialization.
Compliance Information
RoHS compliant per STMicroelectronics product page. AEC-Q100 qualified for automotive applications.
