Dual DC Motor Driver Using BTN9990LV

Full-Bridge Bidirectional Control and Performance Optimization

1. Overview of BTN9990LV

The BTN9990LV is a high-current half-bridge motor driver IC from Infineon based on Smart Power Technology. It is designed for reliable DC motor control in automotive and industrial applications.

Key Features:

• Type: Half-Bridge Motor Driver

• Operating voltage: 5.5 V – 40 V

• High output current capability (up to ±75 A peak)

• Integrated protections:

  • Overcurrent protection

  • Overtemperature protection

  • Undervoltage lockout

  • Short-circuit protection

• Supports high-frequency PWM

• Logic-level compatible (3.3 V and 5 V microcontrollers)

2. Full-Bridge Configuration Using BTN9990LV

Since BTN9990LV is a half-bridge device, a full-bridge (H-bridge) requires two BTN9990LV ICs per motor.

IC Requirement:

• 1 bidirectional DC motor → 2 × BTN9990LV

• 2 bidirectional DC motors → 4 × BTN9990LV

This configuration allows complete control of motor direction, speed, and braking.

3. Operating Principle of Bidirectional Full-Bridge

A full-bridge enables:

• Forward rotation

• Reverse rotation

• Dynamic braking

• Free-running (coast)

Control Logic Example:

PWM signals are used for speed control, while logic levels define rotation direction.

4. Basic BTN9990LV Circuit Description

Important Pins:

• IN – Logic/PWM input

• EN – Enable pin

• OUT – Motor output

• VS – Motor supply voltage

• GND – Ground

• IS – Current sense output

• SR – Slew rate control

Typical Connections:

• VS → Motor power supply (e.g., 12 V or 24 V)

• GND → System ground

• IN → Microcontroller GPIO/PWM

• EN → Logic HIGH to enable

• OUT → Motor terminal

5. Dual Motor Control Architecture

For two motors:

• Motor 1 → BTN9990LV (A & B)

• Motor 2 → BTN9990LV (C & D)

Each motor has independent PWM and direction control, enabling differential drive or independent speed regulation.

6. Performance Optimization Techniques

6.1 Power Supply Design

• Place bulk capacitors (470 µF – 1000 µF) close to the VS pin

• Add 100 nF ceramic decoupling capacitors

• Use short, wide PCB traces for power paths

✔ Reduces voltage drop and electrical noise

6.2 PWM Configuration

• Recommended PWM frequency: 15 – 25 kHz

  • Above audible range

  • Improved efficiency

• Always use hardware PWM for stable control

6.3 Slew Rate Control (SR Pin)

• Use an external resistor on the SR pin

• Slower slew rate:

  • Lower EMI

  • Reduced thermal stress

• Faster slew rate:

  • Faster motor response

✔ Select based on application requirements

6.4 Current Sensing (IS Pin)

• Use the IS pin to:

  • Monitor motor current

  • Detect motor stall or overload

  • Implement software-based protection

• Apply ADC filtering for stable measurements

6.5 Thermal Management

• Use large copper areas on the PCB

• Add thermal vias under the IC

• Attach a heatsink for continuous high-current operation (>5 A)

6.6 Additional Protection

Although BTN9990LV has internal protection:

• Add TVS diodes on the motor supply

• Use fuses or polyfuses

• Implement star-grounding topology

7. Advantages of BTN9990LV Compared to Conventional Drivers

8. Typical Applications

• Differential drive robots

• Automated Guided Vehicles (AGV)

• Line follower robots

• Industrial DC motor control

• Smart actuators

9. Conclusion

A motor driver based on BTN9990LV is a robust and efficient solution for dual DC motor full-bridge bidirectional control. With proper power supply design, PWM configuration, and thermal management, the system achieves:

• High efficiency

• Stable operation

• Reliable protection

• Precise motor control

This makes BTN9990LV ideal for high-performance robotic and industrial motor applications.


Link:
https://drive.google.com/drive/folders/1PoshLd9N2BOwwoIAyyH2I7-uXxUVBLAV?usp=sharing

Writer:
Bintang Adhiyaksa Dani Saputro
+62822-2306-9220
bintangadhiyaksa@gmail.com