L9972-TR - Automotive Dual H-Bridge Driver | STMicroelectronics
MPN: L9972-TR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.25 | $3.25 |
| 10 | $2.92 | $29.20 |
| 100 | $2.6 | $260.00 |
| 500 | $2.34 | $1,170.00 |
| 1,000 | $2.08 | $2,080.00 |
L9972-TR Overview
A dual H-bridge driver is a power management IC that contains two full H-bridge circuits, each consisting of four power transistors (typically MOSFETs) arranged to control the direction and speed of a DC motor by selectively switching the polarity of the voltage applied to the motor terminals. This configuration allows for forward, reverse, brake, and coast operations, making it a fundamental building block in motor control systems. In the broader system hierarchy, the L9972-TR sits within the motor driver category, which is part of the power management IC family, ultimately contributing to the electromechanical actuation layer of automotive and industrial systems.
Key features of the L9972-TR include a low quiescent current of 50 µA in standby mode, which is critical for battery-powered automotive applications to minimize drain when the ignition is off. The device also provides overcurrent, overtemperature, and undervoltage lockout protection, ensuring robust operation in harsh environments. The SPI interface allows for advanced diagnostics and configuration, enabling real-time monitoring of load conditions and fault status. The PowerSO-20 package offers a thermal resistance of 35 °C/W, facilitating heat dissipation in high-current applications.
From a technical architecture perspective, the L9972-TR employs a CMOS process with integrated power MOSFETs, eliminating the need for external freewheeling diodes in many applications. The H-bridge outputs are designed to handle inductive loads with built-in flyback protection, reducing external component count and simplifying PCB layout. The SPI interface operates at up to 5 MHz, providing fast communication with a microcontroller for precise motor control and diagnostic feedback.
Typical applications include automotive power window lifts, seat adjustment motors, mirror adjustment, and HVAC flap control. The device is also suitable for industrial automation, robotics, and small appliance motor drives where bidirectional control and diagnostic capabilities are required. Its wide supply voltage range and robust protection features make it a versatile choice for 12V and 24V systems.
When designing with the L9972-TR, ensure adequate PCB copper area for the exposed pad to maintain junction temperature below the maximum rating. The SPI interface should be isolated from high-current traces to prevent noise coupling, and a bulk capacitor of at least 100 µF should be placed near the supply pins to handle inrush currents during motor start-up.
Drop-in alternatives for L9972-TR — 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 L9972-TR (same form factor and footprint) — differing in Operating Temperature Range, Quiescent Current (Standby), Thermal Resistance (junction-to-ambient).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
L9973-TR
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.08 / Unit
View Datasheet →DRV8842
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
VNH5019A
⚡ Same Package ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
L9972-TR Maximum Ratings & Electrical Characteristics
| Supply Voltage Range | 5.5 V to 36 V |
| Output Current per Channel | 1.2 A (continuous) |
| Number of H-Bridges | 2 |
| Control Interface | SPI |
| Quiescent Current (Standby) | 50 µA |
| Overcurrent Protection | Yes |
| Overtemperature Protection | Yes |
| Undervoltage Lockout | Yes |
| Package | PowerSO-20 |
| Mounting Type | Surface Mount |
| Operating Temperature Range | -40°C to +150°C |
| Thermal Resistance, Junction-to-Ambient | 35 °C/W |
| SPI Clock Frequency | 5 MHz (max) |
| RoHS Status | Compliant |
| AEC-Q100 Qualified | Yes |
L9972-TR Pin Configuration
| Pin 1 | OUT1 — H-bridge 1 output |
| Pin 2 | OUT2 — H-bridge 1 output |
| Pin 3 | VS — Supply voltage |
| Pin 4 | GND — Ground |
| Pin 5 | OUT3 — H-bridge 2 output |
| Pin 6 | OUT4 — H-bridge 2 output |
| Pin 7 | GND — Ground |
| Pin 8 | CSN — SPI chip select (active low) |
| Pin 9 | SCK — SPI clock |
| Pin 10 | SDI — SPI data input |
| Pin 11 | SDO — SPI data output |
| Pin 12 | EN — Enable input |
| Pin 13 | GND — Ground |
| Pin 14 | VS — Supply voltage |
| Pin 15 | OUT5 — H-bridge 2 output |
| Pin 16 | OUT6 — H-bridge 2 output |
| Pin 17 | GND — Ground |
| Pin 18 | OUT7 — H-bridge 1 output |
| Pin 19 | OUT8 — H-bridge 1 output |
| Pin 20 | VS — Supply voltage |
Typical Applications
L9972-TR is suitable for 6 applications: Automotive Power Window Lift, Seat Adjustment Motor, HVAC Flap Control, Industrial Automation, Robotics, Small Appliance Motor Drive.
Automotive Power Window Lift
The L9972-TR drives the DC motor for power windows, providing bidirectional control and diagnostic feedback via SPI. Its 1.2A output current and 5.5V-36V supply range match typical window lift motors. The low standby current of 50 µA minimizes battery drain when the ignition is off. Overcurrent and overtemperature protection ensure reliable operation in harsh automotive environments. The SPI interface allows the body control module to monitor motor current and detect obstructions, enhancing safety.
Recommended
Seat Adjustment Motor
The L9972-TR controls seat position motors, enabling forward/reverse movement with precise speed control. Its dual H-bridge can drive two motors independently, such as for seat base and backrest. The wide supply voltage range accommodates 12V automotive systems. The SPI interface provides real-time diagnostics, allowing the ECU to detect stall conditions and prevent damage. The PowerSO-20 package with exposed pad ensures thermal management during continuous operation.
Recommended
HVAC Flap Control
The L9972-TR drives the DC motors that adjust HVAC air flaps, providing bidirectional control for temperature and airflow regulation. Its 1.2A output current is sufficient for small flap motors, and the SPI interface allows the HVAC controller to read position feedback from external sensors. The device's protection features prevent damage from stalled motors, common in flap systems. The low quiescent current is beneficial for reducing battery drain in parked vehicles.
Recommended
Industrial Automation
In industrial automation, the L9972-TR drives small DC motors for conveyor belts, actuators, and robotic arms. Its 5.5V-36V supply range supports 24V industrial systems. The SPI interface enables integration with PLCs or microcontrollers for precise speed and direction control. The device's robust protection features ensure reliable operation in factory environments with electrical noise. The PowerSO-20 package allows for compact PCB designs in control cabinets.
Recommended
Robotics
The L9972-TR is used in robotics to drive DC motors for wheel movement, arm joints, and grippers. Its dual H-bridge allows independent control of two motors, enabling differential drive for mobile robots. The SPI interface provides high-speed communication for real-time control loops. The device's low quiescent current is advantageous for battery-powered robots. Protection features prevent damage from motor stalls or overcurrent conditions during operation.
Recommended
Small Appliance Motor Drive
The L9972-TR drives motors in small appliances such as fans, pumps, and kitchen gadgets. Its 1.2A output current is suitable for small DC motors, and the wide supply voltage range supports both 12V and 24V systems. The SPI interface allows for advanced features like speed control and diagnostics. The device's protection features ensure safe operation in consumer products. The PowerSO-20 package is compact enough for space-constrained appliance designs.
Recommended
Recommended Products Summary
Engineering reference data for L9972-TR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | L9973-TR | DRV8842 | VNH5019A |
|---|---|---|---|---|
| Package | PowerSO-20 | PowerSO-20 | PowerSO-20 | PowerSO-20 |
| Brand | STMicroelectronics | STMicroelectronics | Texas Instruments | STMicroelectronics |
| Number of H-Bridges | 2 | 1 | 2 | 2 |
| Output Current per Channel | 1.2 A | 1.2 A | 2.5 A | 30 A |
| Supply Voltage Range | 5.5V to 36V | 5.5V to 36V | 8V to 45V | 5.5V to 36V |
| Control Interface | SPI | SPI | SPI | PWM |
| Quiescent Current (Standby) | 50 µA | 50 µA | 10 µA | 5 µA |
| AEC-Q100 Qualified | Yes | Yes | Yes | Yes |
Key Differentiators
- Dual H-bridge in a single package (vs L9973-TR)
- SPI interface for diagnostics (vs VNH5019A)
- Lower quiescent current (vs DRV8842)
Design Notes
The PowerSO-20 package has a junction-to-ambient thermal resistance of 35 °C/W. At 1.2A per channel and 12V supply, power dissipation can reach 2.9W per channel, causing a temperature rise of 101.5°C. Ensure adequate PCB copper area (at least 2 square inches) and thermal vias under the exposed pad to keep junction temperature below 150°C.
Place a 100 µF electrolytic capacitor and a 0.1 µF ceramic capacitor close to the VS pins to handle inrush currents during motor start-up and to filter high-frequency noise. Keep SPI traces short and shielded from high-current motor traces to prevent noise coupling. Use a ground plane to minimize EMI.
Do not exceed the absolute maximum supply voltage of 40V. Ensure the SPI chip select (CSN) is pulled high during power-up to avoid unintended communication. When driving inductive loads, the built-in flyback protection is sufficient, but for high-current applications, external Schottky diodes may be added to reduce voltage spikes.
Compliance Information
RoHS compliant and AEC-Q100 qualified per STMicroelectronics product page. Halogen-free status not specified in provided data.