onsemi LB11961-W-AH: Datasheet, Pinout, and Application Circuit Guide

The onsemi LB11961-W-AH is a single-channel H-bridge driver IC designed for precise control of DC motors and solenoids in a wide range of consumer and industrial applications. Its integration of control logic, protection features, and power output stages into a single package makes it an efficient solution for driving inductive loads. This guide provides an overview of its key specifications, pinout configuration, and a typical application circuit.

Datasheet Overview and Key Features

According to its datasheet, the LB11961-W-AH is engineered for reliability and performance. Its primary function is to control the direction and speed of a DC motor by enabling bidirectional control through its H-bridge configuration. Key features highlighted in the datasheet include:

Low Saturation Voltage: The output stage features low saturation voltage (typical VCE(sat) = 0.5V max at Io=1.0A), which minimizes power dissipation and improves overall system efficiency, making it suitable for battery-powered devices.

Built-in Protection Circuits: The IC incorporates crucial protection mechanisms, including thermal shutdown (TSD) to prevent damage from overheating and overcurrent protection (OCP) that safeguards the outputs from short-circuit conditions.

Wide Operating Voltage Range: It supports a broad supply voltage range (VCC = 4.5V to 16V), accommodating various power supply conditions.

TTL/CMOS Compatible Inputs: The control inputs (IN1, IN2) are compatible with standard logic levels, allowing for direct interfacing with microcontrollers (MCUs) or logic circuits without needing level shifters.

Pinout Configuration

Understanding the pinout is essential for proper PCB layout and circuit design. The LB11961-W-AH is available in a compact HSOP-10 package.

A typical pinout description is as follows:

1. OUT1: Bridge output 1. Connects to one terminal of the motor.

2. VCC: Power supply pin for the output stage. Must be decoupled with a capacitor close to the pin.

3. OUT2: Bridge output 2. Connects to the other terminal of the motor.

4. GND: Ground pin.

5. IN2: Control input 2. Determines the motor's direction and mode in combination with IN1.

6. VREF: Reference voltage pin for the internal circuit.

7. IN1: Control input 1.

8. VM: Monitor pin for the motor power supply.

9. NC: No connection.

10. VCC: Power supply pin for the control logic.

Truth Table:

| IN1 | IN2 | OUT1 | OUT2 | Mode |

|-----|-----|------|------|---------------|

| H | L | H | L | Forward |

| L | H | L | H | Reverse |

| L | L | Z | Z | Stop (Fast Decay) |

| H | H | L | L | Brake |

Typical Application Circuit Guide

A basic application circuit for bidirectional DC motor control is straightforward. The core components include the LB11961-W-AH IC, a DC power source (Vmot), a microcontroller, and decoupling capacitors.

How to Implement:

1. Power Supply: Connect the `VCC` pins to the motor power supply (Vmot, within 4.5V-16V). Place a large electrolytic capacitor (e.g., 100µF) near the Vmot source and a small ceramic capacitor (e.g., 0.1µF) directly between the `VCC` and `GND` pins to suppress noise and stabilize the supply.

2. Motor Connection: Connect the DC motor between the output pins `OUT1` and `OUT2`.

3. Control Logic: Connect the `IN1` and `IN2` pins directly to GPIO pins of an MCU. The motor direction and state are controlled by applying the logic levels as defined in the truth table above.

4. Enable Pin (VREF): This pin is often connected to `VCC` via a resistor for normal operation, but its configuration should be verified against the datasheet for specific use cases.

5. Grounding: Ensure a solid, low-impedance ground connection for the `GND` pin.

This simple setup allows for full forward, reverse, brake, and stop control of the motor, with the IC's internal protection features actively monitoring for faults.

ICGOODFIND: The onsemi LB11961-W-AH is a highly integrated and robust H-bridge driver, offering a compelling combination of low power loss, comprehensive protection, and simple control interface. It is an excellent choice for designers seeking a reliable solution for driving small to medium DC motors in applications like office automation equipment, robotics, toys, and automotive subsystems.

Keywords: H-Bridge Driver, DC Motor Control, Low Saturation Voltage, Thermal Shutdown, Bidirectional Control