Infineon AUIRS2181STR High and Low Side Driver IC: Features, Applications, and Benefits

In the realm of power electronics, efficient and reliable switching of MOSFETs and IGBTs is paramount. The Infineon AUIRS2181STR stands out as a specialized high-voltage, high-speed power MOSFET and IGBT driver, engineered to control both high-side and low-side switches in a half-bridge configuration. This integrated circuit (IC) is a cornerstone in modern power conversion systems, offering a blend of performance, integration, and protection that simplifies design and enhances system robustness.

Key Features of the AUIRS2181STR

The AUIRS2181STR is packed with advanced features that make it a preferred choice for designers. Its floating channel designed for bootstrap operation allows it to drive N-channel power MOSFETs or IGBTs on the high side, operating at voltages up to 600V. This high voltage capability is crucial for industrial and automotive applications. The driver incorporates a built-in dead time control (DTD), which is essential for preventing shoot-through currents—a catastrophic condition where both high-side and low-side switches conduct simultaneously, potentially destroying the circuit.

Furthermore, it boasts excellent immunity against negative voltage transients (dv/dt immunity), ensuring stable operation in noisy electrical environments. The matched propagation delays between the two channels minimize output distortion. With a 3.3V and 5V input logic compatible interface, it can be directly driven by microcontrollers or DSPs without requiring additional level-shifting circuitry. The robust under-voltage lockout (UVLO) feature for both channels safeguards the power switches by ensuring they only operate with sufficient gate drive voltage.

Primary Applications

The versatility of the AUIRS2181STR makes it suitable for a wide array of applications. It is predominantly used in motor control systems, including those for industrial automation, robotics, and consumer appliances like washing machines and air conditioners. Its high-speed switching capability is also ideal for switch-mode power supplies (SMPS) and uninterruptible power supplies (UPS), where efficiency and reliability are critical.

A significant application domain is in the automotive industry, where it is used in systems like electronic power steering (EPS), engine management, and DC-AC inverters. Its ability to handle high voltages and its robust design meet the stringent requirements of automotive environments. Additionally, it finds use in lighting solutions, such as driving HID lamps, and in full-bridge and three-phase inverter topologies.

Tangible Benefits for Designers

Utilizing the AUIRS2181STR offers numerous advantages. Its high level of integration reduces component count on the PCB, leading to a smaller footprint, lower overall system cost, and increased reliability. The integrated dead time and protection features simplify the design process, reducing development time and mitigating risks associated with circuit failure.

The driver's high noise immunity ensures stable operation even in the presence of significant switching noise and ground fluctuations, which is a common challenge in high-power circuits. This results in higher system efficiency and longevity. By providing strong gate drive currents (typical peak output current of 1.9A for both sourcing and sinking), it enables fast switching transitions of the power devices, which minimizes switching losses—a key factor for improving the overall efficiency of the power conversion system.

ICGOODFIND Summary

The Infineon AUIRS2181STR is a robust and highly integrated high- and low-side driver IC that simplifies the design of efficient half-bridge power stages. Its combination of high-voltage operation, built-in protections like dead-time control and UVLO, and logic-level compatibility makes it an exceptional solution for motor drives, power supplies, and automotive systems, ensuring both performance and reliability.

Keywords:

1. Half-Bridge Driver

2. Bootstrap Operation

3. Dead Time Control

4. High-Voltage Switching

5. Motor Control