Infineon IR21844STRPBF: High- and Low-Side Driver IC for Power MOSFETs and IGBTs
In the realm of power electronics, efficiently and safely driving the switching elements—typically power MOSFETs or IGBTs—in a half-bridge configuration is a fundamental challenge. The Infineon IR21844STRPBF is a high-voltage, high-speed power MOSFET and IGBT driver engineered specifically to meet this challenge. This robust integrated circuit serves as a pivotal component in applications ranging from motor drives and switch-mode power supplies (SMPS) to industrial inverters, simplifying design while enhancing system reliability and performance.
A core strength of the IR21844 lies in its ability to drive both the high-side and low-side switches in a bridge topology. This eliminates the need for a separate, complex bootstrap power supply for the high-side driver section. The IC incorporates a sophisticated level-shift circuit and a built-in bootstrap diode, allowing it to efficiently generate the required floating supply voltage for the high-side channel. This integration significantly reduces external component count, saves board space, and lowers the overall bill of materials (BOM).
The driver is designed for robustness and speed. It features independent input logic for each channel, providing designers with greater flexibility and control over the switching patterns. The outputs are capable of delivering high peak current pulses (up to 1.5A source/2.0A sink), enabling very fast switching transitions of the power devices. This minimizes switching losses, which is critical for achieving high efficiency, especially in high-frequency applications. Furthermore, the IC's fast propagation delays (typically 120ns) and matched timing between channels ensure precise control, preventing potential shoot-through currents that could damage the power stage.
Protection is a cornerstone of the IR21844's design. It includes integrated deadtime control (typ. 540ns), which automatically inserts a small delay between the turn-off of one switch and the turn-on of its complementary partner, providing a crucial safeguard against shoot-through. The IC is also equipped with undervoltage lockout (UVLO) protection for both the high-side and low-side driver sections. If the supply voltage drops below a specified threshold, the outputs are disabled, preventing the power MOSFETs or IGBTs from operating in a linear region, which could lead to excessive heating and failure.
Housed in a compact yet thermally efficient 8-lead SOIC package, the IR21844STRPBF is suitable for automated PCB assembly and can operate over a wide temperature range, making it adaptable to demanding industrial environments. Its high noise immunity, thanks to Schmitt-triggered inputs and robust level-shifting technology, ensures stable operation even in electrically noisy power circuits.
ICGOOODFIND: The Infineon IR21844STRPBF is an industry-proven, highly integrated driver IC that offers a potent combination of high-speed switching, robust protection features, and design simplification. Its ability to independently drive both sides of a bridge with minimal external components makes it an excellent and reliable choice for a vast array of medium to high-power conversion applications.
Keywords: Half-Bridge Driver, Bootstrap Circuit, High-Side Switching, Undervoltage Lockout (UVLO), Shoot-Through Protection.
