Infineon IR11672ASTRPBF: A High-Performance DCM and CCM Control IC for SMPS
The relentless pursuit of higher efficiency, reliability, and power density in Switch-Mode Power Supplies (SMPS) has driven significant innovation in control IC technology. At the forefront of this advancement is the Infineon IR11672ASTRPBF, a highly specialized control IC engineered to master both Discontinuous and Continuous Conduction Modes (DCM & CCM) in synchronous rectification (SR) circuits.
Synchronous rectification, which replaces power-wasting diode voltage drops with low-RDS(on) MOSFETs, is critical for modern high-efficiency power conversion. However, effectively controlling the SR MOSFET's switching across different operational modes presents a formidable challenge. The IR11672ASTRPBF is designed explicitly to solve this, serving as a secondary-side intelligent controller that drives an SR MOSFET in flyback, forward, and LLC resonant converters.
A key strength of this IC lies in its robust and autonomous operation. It functions independently, without requiring a direct electrical connection to the primary-side controller. This simplifies design and enhances system reliability. The device self-generates the necessary gate drive signals by precisely monitoring the voltage across the drain and source of the SR MOSFET (Vds). Its advanced sensing circuitry can detect the minute negative voltage that appears when the MOSFET's body diode begins to conduct, triggering a turn-on signal with ultra-fast response times. Crucially, it also features a precise, programmable termination algorithm to determine the optimal moment to turn off the SR MOSFET, minimizing the risk of cross-conduction and reverse current flow, which are detrimental to efficiency.
The IR11672ASTRPBF excels in its versatility, seamlessly handling the complexities of both DCM and CCM operations without external mode selection. In DCM, it ensures clean and efficient switching cycles. In CCM, where the current never falls to zero, its sophisticated control logic is vital for preventing shoot-through and maintaining stability. Furthermore, the IC incorporates comprehensive protection features, including Vds over-voltage protection and a negative Vds clamp, safeguarding the SR MOSFET under abnormal conditions.
By maximizing the efficiency gains from synchronous rectification across a wide load range, this IC enables power supplies to meet stringent international energy standards. It reduces thermal stress, allows for the use of smaller heatsinks and form factors, and ultimately contributes to a more reliable and compact end product.
ICGOOODFIND: The Infineon IR11672ASTRPBF stands out as a critical enabler for next-generation SMPS designs. Its high-performance, autonomous control for synchronous rectification in both DCM and CCM significantly boosts efficiency, simplifies design complexity, and enhances overall system robustness, making it an superior choice for demanding power applications.
Keywords: Synchronous Rectification, DCM/CCM Control, SMPS, High-Efficiency, Secondary-Side Controller
