Infineon BTS728L2: A High-Current PROFET™ Smart High-Side Power Switch

In the realm of automotive and industrial electronics, efficient and robust power management is paramount. The Infineon BTS728L2 stands out as a premier solution, representing a significant advancement in high-side power switching technology. As part of Infineon's esteemed PROFET™ (Protected FET) family, this device is engineered to handle high-current loads up to 42A with exceptional reliability and integrated intelligence, making it an ideal choice for demanding applications.

At its core, the BTS728L2 is a quad-channel smart high-side switch. Each of the four channels can independently control resistive, capacitive, or inductive loads, such as motors, valves, heaters, and lamps. A key feature is its very low typical on-state resistance (RDS(on)) of just 3.5 mΩ per channel. This minimal resistance is crucial for minimizing power dissipation and thermal losses, leading to higher system efficiency and reduced need for complex heat sinking.

The "smart" capabilities of the BTS728L2 are what truly set it apart. It provides a comprehensive suite of diagnostic and protection features that are essential for designing fail-safe systems. These include:

Load Current Feedback: An analog proportional current sense signal for each channel enables precise load monitoring and diagnosis.

Overload and Short-Circuit Protection: The device automatically limits the output current in case of a fault, protecting both the switch and the load.

Overtemperature Shutdown: An integrated thermal shutdown mechanism prevents damage from excessive heat.

Overvoltage Protection (including load dump): Safeguards the switch from voltage transients common in automotive environments.

Open-Load Detection: Detects whether a load is disconnected both in on-state and off-state, which is critical for safety diagnostics.

Furthermore, the device is designed for robust performance in harsh environments, featuring high immunity to electrostatic discharge (ESD) and a wide operating voltage range. Its reverse battery protection ensures the circuit remains undamaged if the power supply connections are accidentally reversed. Control is achieved via a 3.3V/5V compatible CMOS logic input for each channel, allowing for easy interfacing with microcontrollers.

The BTS728L2 finds its primary applications in the automotive sector, perfect for driving loads in body control modules (e.g., seat heaters, window lifters, lighting) and in industrial automation systems where multi-channel control and diagnostics are required.

ICGOOODFIND: The Infineon BTS728L2 PROFET™ is a highly integrated, intelligent quad-channel switch that delivers superior power density, unmatched diagnostic capabilities, and robust protection. It simplifies design, enhances system reliability, and provides the critical feedback needed for next-generation automotive and industrial applications.

Keywords: High-Current Switch, PROFET™, Diagnostic Features, On-State Resistance (RDS(on)), Automotive Grade.