Infineon BTS4140N High-Side Power Switch: Datasheet, Application Circuit, and Features Overview
The Infineon BTS4140N is a versatile and robust intelligent high-side power switch designed to control a wide range of resistive and inductive loads in automotive and industrial applications. Housed in a compact PG-TO-252-4 (DPAK) package, this device integrates a vertical power MOSFET with advanced protection and diagnostic features, making it a cornerstone for reliable electronic switching.
Key Features Overview
The BTS4140N stands out due to its integration of control logic, power stage, and protection circuits into a single chip. Its key features include:
High Current Capability: It can handle a continuous output current of up to 140 mA, with a maximum operating voltage of 45 V, making it suitable for 12V and 24V systems.
Low Quiescent Current: The device features an extremely low standby current, which is crucial for battery-powered applications where minimizing energy drain is paramount.
Integrated Protection Functions: A primary advantage is its comprehensive suite of on-chip protections. These include overload protection, short-circuit protection, overtemperature shutdown with automatic restart, and overvoltage protection (including load-dump recovery).
Diagnostic Feedback: The device provides a status feedback pin (IN/EN), which can be monitored by a microcontroller to diagnose conditions like open-load (in off-state) and overtemperature.
Enhanced ESD Robustness: It offers high electrostatic discharge (ESD) protection, ensuring durability in harsh electrical environments.
Green Product (RoHS compliant): It is manufactured with environmentally friendly materials.
Application Circuit
The BTS4140N is designed for ease of use. A typical application circuit is straightforward, requiring very few external components.
1. Load Connection: The controlled load (e.g., a lamp, relay, solenoid, or heating element) is connected between the output pin (OUT) and ground.
2. Power Supply: The supply voltage (Vs) is connected directly to the device's Vbb pin.
3. Control Input: A microcontroller's GPIO pin is connected to the IN/EN pin. Applying a high-level logic signal (typically > 3.5V) turns the power switch ON, allowing current to flow to the load. A low-level signal (< 1.5V) turns it OFF.
4. Optional Components: While the IC is largely self-protected, a small series resistor (e.g., 10kΩ) on the IN/EN pin is often used to limit current. A pull-down resistor may be added to ensure a defined OFF-state during microcontroller startup or reset. A decoupling capacitor (e.g., 100nF) placed close to the Vbb pin is recommended to suppress voltage spikes and noise on the supply line.
This simple interface allows designers to replace discrete solutions (like a MOSFET, driver, and several protection components) with a single, reliable device, saving board space and simplifying design.
Datasheet Essentials
The BTS4140N datasheet is the ultimate source of truth for designers. Key sections to focus on include:
Absolute Maximum Ratings: Understanding the limits for parameters like supply voltage, output current, and temperature is critical to avoid device destruction.
Thermal Resistance: The Junction-to-Ambient (RthJA) value is vital for calculating power dissipation and ensuring the junction temperature does not exceed its maximum limit during operation.
Characteristic Curves: Graphs showing output current vs. supply voltage, switching times, and temperature behavior provide deep insight into real-world performance.
Application Information: The datasheet offers detailed notes on layout recommendations, such as using a sufficient copper area for the GND pin to act as a heat sink, which is crucial for thermal performance.
The Infineon BTS4140N is an efficient and highly integrated solution for medium-power switching tasks. Its robust built-in protection features and diagnostic capability significantly enhance system reliability while reducing component count and design complexity. It is an excellent choice for automotive body electronics, industrial automation, and any application demanding a compact and dependable high-side switch.
Keywords:
High-Side Switch
Power Switch
Infineon BTS4140N
Overcurrent Protection
Application Circuit
