L9975 - Automotive Dual H-Bridge Motor Driver | STMicroelectronics
MPN: L9975 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.25 | $3.25 |
| 10 | $2.95 | $29.50 |
| 100 | $2.65 | $265.00 |
| 500 | $2.4 | $1,200.00 |
| 1,000 | $2.2 | $2,200.00 |
L9975 Overview
A motor driver is an integrated circuit that translates low-power control signals from a microcontroller into the higher voltage and current needed to drive a motor. In the system hierarchy, the L9975 sits between the MCU and the motor, acting as a power amplifier and protection interface. It is a key component in automotive body control modules, where it controls window lifts, mirror adjustment, and seat positioning.
Key features of the L9975 include a low quiescent current of 10 uA in standby mode, making it suitable for always-on automotive modules. It offers overcurrent, overtemperature, and short-circuit protection, ensuring reliable operation in harsh environments. The device also features a serial peripheral interface (SPI) for diagnostics and control, allowing the MCU to read fault status and configure the driver.
The L9975 uses a standard H-bridge topology with integrated freewheeling diodes, eliminating the need for external clamping diodes. Its SPI interface enables advanced diagnostics, including open-load detection and overcurrent reporting. The device is AEC-Q100 qualified, meeting the stringent reliability requirements of automotive electronics.
Typical applications include automotive window lift systems, mirror adjustment, seat positioning, and HVAC damper control. The wide supply voltage range and robust protection make it ideal for direct connection to the vehicle battery, withstanding load-dump and cold-crank transients.
When designing with the L9975, ensure proper PCB layout with adequate copper area for thermal dissipation. The PowerSO-20 package has a thermal resistance of 35 C/W, so at maximum current and high ambient temperatures, a heatsink or large copper pour is recommended. Additionally, place the SPI lines with proper filtering to avoid noise coupling from the motor lines.
Drop-in alternatives for L9975 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with L9975 (same form factor and footprint) — differing in Package, AEC-Q100 Qualification, Diagnostics, Operating Temperature Range, Output Current per Channel.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
L9975A
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
L9958
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$6.2 / Unit
View Datasheet →L9975 Maximum Ratings & Electrical Characteristics
| Supply Voltage Range | 5.5 V to 36 V |
| Output Current per Channel | 1.2 A |
| Number of H-Bridges | 2 |
| Control Interface | SPI |
| Quiescent Current (Standby) | 10 uA |
| Operating Temperature Range | -40C to +150C |
| Package | PowerSO-20 |
| Mounting Type | Surface Mount |
| Protection Features | Overcurrent, Overtemperature, Short-Circuit |
| Diagnostics | SPI fault reporting, open-load detection |
| AEC-Q100 Qualification | Yes |
| RoHS Status | Compliant |
| Thermal Resistance (theta_JA) | 35 C/W |
| Output Type | Dual H-Bridge |
| Motor Types Supported | DC, Stepper |
L9975 Pin Configuration
| Pin 1 | VS — Supply voltage |
| Pin 2 | OUT1 — Motor output 1 |
| Pin 3 | OUT2 — Motor output 2 |
| Pin 4 | GND — Ground |
| Pin 5 | OUT3 — Motor output 3 |
| Pin 6 | OUT4 — Motor output 4 |
| Pin 7 | GND — Ground |
| Pin 8 | CSN — Chip select (active low) |
| Pin 9 | SCK — SPI clock |
| Pin 10 | SDI — SPI data input |
| Pin 11 | SDO — SPI data output |
| Pin 12 | GND — Ground |
| Pin 13 | DIAG — Diagnostic output |
| Pin 14 | EN — Enable input |
| Pin 15 | GND — Ground |
| Pin 16 | VS — Supply voltage |
| Pin 17 | OUT5 — Motor output 5 |
| Pin 18 | OUT6 — Motor output 6 |
| Pin 19 | GND — Ground |
| Pin 20 | VS — Supply voltage |
Typical Applications
L9975 is suitable for 6 applications: Automotive Window Lift, Mirror Adjustment, Seat Positioning, HVAC Damper Control, Stepper Motor Control, Industrial Automation.
Automotive Window Lift
The L9975 drives the DC motor for window lift systems. Its 1.2A output current is sufficient for small window motors, and the SPI interface allows precise control and diagnostics. The wide supply voltage range handles battery transients, and the low standby current minimizes battery drain when the window is not in use. The overcurrent and overtemperature protection ensure reliable operation in harsh automotive environments.
Recommended
Mirror Adjustment
The L9975 is used to control the small DC motors that adjust side mirrors. Its dual H-bridge configuration allows independent control of two motors, enabling both horizontal and vertical adjustment. The SPI interface provides feedback on motor position and fault conditions. The device's low quiescent current is beneficial for always-on mirror modules, and its AEC-Q100 qualification ensures reliability in extreme temperatures.
Recommended
Seat Positioning
The L9975 drives the motors that adjust seat position, including forward/backward and recline. Its dual H-bridge can control two motors simultaneously, and the SPI interface allows the MCU to monitor current and detect obstructions. The wide supply voltage range ensures operation during engine start, and the protection features prevent damage from stalled motors.
Recommended
HVAC Damper Control
The L9975 controls the DC motors that adjust HVAC dampers. Its low quiescent current is ideal for always-on climate control modules, and the SPI interface allows precise positioning. The device's overcurrent protection prevents damage if a damper jams. The wide temperature range ensures reliable operation in the passenger compartment.
Recommended
Stepper Motor Control
The L9975 can drive a bipolar stepper motor by using both H-bridges. The SPI interface allows the MCU to generate step sequences and control speed. The device's current capability of 1.2A per phase is suitable for small stepper motors used in instrument clusters or headlamp leveling. The protection features ensure reliable operation.
Recommended
Industrial Automation
The L9975 can be used in industrial automation for controlling small DC motors in valves, actuators, and conveyors. Its wide supply voltage range and robust protection make it suitable for 24V industrial systems. The SPI interface allows integration with PLCs or microcontrollers. The device's AEC-Q100 qualification also ensures high reliability in industrial environments.
Recommended
Recommended Products Summary
Engineering reference data for L9975 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | L9975A | L9958 | DRV8842 |
|---|---|---|---|---|
| Package | PowerSO-20 | PowerSO-20 | PowerSO-20 | HTSSOP-28 |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | Texas Instruments |
| Supply Voltage Range | 5.5V to 36V | 5.5V to 36V | 5.5V to 36V | 8V to 45V |
| Output Current per Channel | 1.2A | 1.2A | 8.5A | 2.5A |
| Number of H-Bridges | 2 | 2 | 1 | 2 |
| Control Interface | SPI | SPI | SPI | PWM |
| Quiescent Current (Standby) | 10 uA | 10 uA | 20 uA | 1.5 mA |
| AEC-Q100 Qualified | Yes | Yes | Yes | No |
Key Differentiators
- Dual H-bridge in a single package (vs L9958)
- Low standby quiescent current of 10 uA (vs DRV8842)
- AEC-Q100 qualified (vs DRV8842)
Design Notes
The PowerSO-20 package has a thermal resistance of 35 C/W. At maximum output current (1.2A per channel) and a supply voltage of 36V, power dissipation can be significant. For example, with a 12V motor and 1.2A, the power dissipation is approximately 14.4W, leading to a junction temperature rise of 504C. Ensure adequate PCB copper area or a heatsink to keep the junction temperature within the -40C to +150C range.
Place the supply decoupling capacitors (100 nF and 10 uF) as close as possible to the VS pins. The motor outputs should have proper filtering to reduce EMI. Use a ground plane to minimize noise coupling to the SPI lines. Keep the SPI traces short and shielded from the motor lines.
Do not exceed the absolute maximum supply voltage of 40V. Ensure the SPI lines are properly pulled up or down to avoid floating inputs. The EN pin must be driven high to enable the outputs; otherwise, the outputs are in high-impedance state. Also, verify the logic levels of the SPI interface match the MCU's voltage.
Compliance Information
AEC-Q100 qualified per STMicroelectronics product page. RoHS compliant. Halogen-free status not specified in the provided data.