High-Current Half-Bridge Motor Driver Using the Infineon BTS7960 IC
Controlling high-power DC motors and other inductive loads like solenoids or lamps requires robust and efficient driver circuitry. A common and powerful solution for bidirectional control is the H-Bridge topology. While a full H-Bridge uses four switches, a Half-Bridge configuration is often employed when only unidirectional control is needed or when two can be combined to form the full bridge. The Infineon BTS7960 IC is a cornerstone component for building such high-performance motor drivers.
The BTS7960 is not a simple switch; it is a fully integrated high-current half-bridge. It combines a P-channel high-side MOSFET and an N-channel low-side MOSFET in one package. This intelligent integration is pivotal. The P-channel MOSFET on the high side simplifies the driving circuitry because, unlike an N-channel MOSFET, it does not require a charge pump or bootstrap circuit to achieve a gate voltage higher than the supply voltage. Each MOSFET is protected by its own freewheeling diode, which is essential for handling the back-electromotive force (back-EMF) generated when the motor is decelerated or its direction is changed.
The key to the BTS7960's capability lies in its internal charge pump for the high-side switch and the integrated driver logic. This architecture allows it to handle a continuous current of up to 43A and peak currents even higher, making it suitable for demanding applications in robotics, industrial automation, and automotive systems. The IC features separate pins for enabling each half of the bridge (INH) and for providing the PWM input signal (IN), offering flexible control. Crucially, it also provides comprehensive diagnostic and protection features, including overtemperature shutdown, overcurrent protection, and undervoltage lockout, which safeguard both the driver and the motor from damage under fault conditions.
A typical application involves pairing two BTS7960 ICs to form a complete H-Bridge motor driver. One IC controls one half of the bridge (e.g., the high-side and low-side for the motor's "A" side), and a second identical IC controls the other half. By applying PWM signals to the IN inputs of these ICs in the correct sequence, the microcontroller can effortlessly command the motor to run forward, backward, brake, or coast. The high level of integration means the external component count remains very low, typically requiring just a few decoupling capacitors and current-sensing resistors, leading to a compact and reliable PCB design.
The Infineon BTS7960 is an exceptional IC for building high-power motor drives. Its integration of power MOSFETs, drivers, and protection circuits into a single package dramatically reduces design complexity and board space. Its ability to handle very high currents with robust built-in safeguards makes it a premier choice for engineers developing reliable and powerful motion control systems in automotive and industrial environments.
Keywords: High-Current, Half-Bridge, BTS7960, Motor Driver, H-Bridge
