L99SM81V - Automotive Stepper Motor Driver | STMicroelectronics
MPN: L99SM81V 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 L99SM81V 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:
L99SM81VTR
β Drop-Inπ Reference alternative (not in catalog)
L99SM81V
β Drop-Inβ 99,999 In Stock
$2.88 / Unit
View Datasheet βL99SM81V Maximum Ratings & Electrical Characteristics
| Supply Voltage Range | 6 V to 28 V |
| Output Current per Phase | 1.2 A |
| Microstepping Resolution | Up to 1/16 step |
| Control Interface | SPI |
| Current Sensing | Integrated, no external sense resistors |
| Protection Features | Overcurrent, overtemperature, undervoltage |
| Standby Current | Low quiescent current in standby |
| Operating Temperature Range | -40Β°C to +150Β°C (junction) |
| Package | PowerSSO-36 |
| Mounting Type | Surface Mount |
| AEC-Q100 Qualification | Yes |
| Motor Type | Bipolar stepper |
| Decay Mode | Programmable |
| Diagnostics | SPI fault reporting |
| RoHS Status | Compliant |
L99SM81V Pin Configuration
| Pin 1 | VS β Motor supply voltage |
| Pin 2 | GND β Ground |
| Pin 3 | OUT1A β Motor phase A output |
| Pin 4 | OUT1B β Motor phase A output |
| Pin 5 | OUT2A β Motor phase B output |
| Pin 6 | OUT2B β Motor phase B output |
| Pin 7 | VDD β Logic supply voltage |
| Pin 8 | SCK β SPI clock |
| Pin 9 | SDI β SPI data input |
| Pin 10 | SDO β SPI data output |
| Pin 11 | CSN β SPI chip select (active low) |
| Pin 12 | EN β Enable pin |
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
L99SM81V is suitable for 6 applications: Headlamp Leveling Systems, HVAC Flap Control, Instrument Cluster Stepper Motors, Adaptive Front Lighting Systems, Electric Parking Brake Actuators, Industrial Automation.
Headlamp Leveling Systems
The L99SM81V drives stepper motors that adjust headlamp beam angle to maintain proper alignment with vehicle load. Its 1.2 A per phase output and microstepping up to 1/16 step enable precise positioning, while the wide 6-28 V supply range handles battery voltage variations. The integrated current sensing and SPI diagnostics allow real-time monitoring of motor health, ensuring reliable operation in harsh automotive environments. AEC-Q100 qualification guarantees performance across -40Β°C to +150Β°C, making it ideal for under-hood or headlamp-adjacent mounting.
Recommended
HVAC Flap Control
In automotive HVAC systems, the L99SM81V precisely positions air distribution flaps to regulate cabin temperature and airflow. Its microstepping capability ensures quiet and smooth operation, reducing audible noise in the cabin. The low standby current helps minimize battery drain when the HVAC is off. The SPI interface allows the climate control unit to adjust flap positions dynamically, and the integrated protection features prevent damage from stalled motors or overcurrent conditions. The wide supply voltage range ensures operation during engine start-stop events.
Recommended
Instrument Cluster Stepper Motors
The L99SM81V drives stepper motors in instrument clusters for gauge indication (speedometer, tachometer). Its high microstepping resolution (up to 1/16 step) provides smooth needle movement, essential for accurate and aesthetically pleasing gauge response. The integrated current sensing eliminates external sense resistors, saving PCB space in compact cluster designs. The SPI interface enables precise control and diagnostics, while the AEC-Q100 qualification ensures long-term reliability in the passenger compartment. The low quiescent current is beneficial for reducing parasitic drain when the vehicle is off.
Recommended
Adaptive Front Lighting Systems
The L99SM81V is used in adaptive front lighting systems (AFS) to adjust headlamp beam patterns based on steering angle and vehicle speed. Its precise microstepping control allows smooth and rapid adjustment of the beam direction, enhancing nighttime visibility. The wide supply voltage range (6-28 V) accommodates voltage fluctuations during engine cranking. The SPI interface provides real-time diagnostics, enabling the system to detect and respond to motor faults. The integrated protection features ensure safe operation in all conditions.
Recommended
Electric Parking Brake Actuators
The L99SM81V can drive stepper motors in electric parking brake (EPB) actuators, providing precise clamping force control. Its high current capability (1.2 A per phase) ensures sufficient torque for brake actuation, while the microstepping allows fine control of the clamping force. The integrated current sensing enables closed-loop force control, and the SPI interface allows the brake control module to monitor motor status. The AEC-Q100 qualification and wide temperature range make it suitable for underbody mounting.
Recommended
Industrial Automation
While designed for automotive, the L99SM81V can be used in industrial automation for precise stepper motor control in applications such as valve positioning and conveyor systems. Its wide supply voltage range and robust protection features make it suitable for industrial environments. The SPI interface allows easy integration with industrial microcontrollers, and the integrated current sensing simplifies design. However, for non-automotive applications, lower-cost alternatives like the DRV8825 may be more cost-effective.
Recommended
Recommended Products Summary
Engineering reference data for L99SM81V β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | L99SM81VTR | DRV8825 |
|---|---|---|---|
| Package | PowerSSO-36 | PowerSSO-36 (same) | HTSSOP-28 (different) |
| Brand | STMicroelectronics | STMicroelectronics | Texas Instruments |
| Supply Voltage Range | 6 V to 28 V | 6 V to 28 V | 8.2 V to 45 V |
| Output Current per Phase | 1.2 A | 1.2 A | 2.5 A |
| Microstepping Resolution | Up to 1/16 step | Up to 1/16 step | Up to 1/32 step |
| Control Interface | SPI | SPI | Step/Direction |
| Current Sensing | Integrated | Integrated | External sense resistors |
| AEC-Q100 Qualification | Yes | Yes | No |
Key Differentiators
- AEC-Q100 qualified for automotive (vs DRV8825)
- Integrated current sensing (vs DRV8825)
- SPI control interface (vs DRV8825)
Design Notes
The L99SM81V in PowerSSO-36 package can dissipate significant power when driving 1.2 A per phase. Ensure adequate PCB copper area, preferably with a thermal pad connected to a large ground plane. For continuous operation at high currents, consider adding vias to improve heat transfer to inner layers. The junction temperature must not exceed 150Β°C; calculate power dissipation based on supply voltage and motor current.
Place decoupling capacitors (e.g., 100 nF ceramic) close to the VS and VDD pins to suppress high-frequency noise. Use a bulk capacitor (e.g., 10 Β΅F) on the motor supply to handle current transients. Keep SPI signal traces short and away from high-current motor traces to avoid noise coupling. A ground plane is recommended for the logic section.
Do not exceed the absolute maximum supply voltage of 28 V. Ensure the SPI interface is properly initialized before enabling the motor outputs. The integrated current sensing eliminates external sense resistors, but the current limit must be programmed correctly via SPI to avoid overcurrent. In standby mode, ensure the EN pin is low to minimize quiescent current.
Compliance Information
AEC-Q100 qualified per STMicroelectronics. RoHS compliant. REACH compliance assumed based on ST policy.
