Both controllers offer a programmable minimum-on-time function to ensure reliable operation over a wide range of switching frequencies.
Infineon’s IR1161L and IR11688S secondary synchronous rectification controllers for SMPS (switch-mode power supply) applications provide direct sensing of MOSFET drain voltage up to 200V, eliminating the need for external voltage dividers. The devices meet 2016 U.S. DOE and EU CoC energy efficiency standards and, when teamed with the company’s OptiMOS and StrongIRFET MOSFETs, can improve efficiency by as much as 3%.
Figure 1: The dual IR11688S is used for LLC-resonant SMPS applications. (Source: Infineon)
The IR1161L targets flyback SMPS designs in chargers and AC/DC adapters, while the dual IR11688S is used for LLC-resonant SMPS applications. Both controllers offer a programmable MOT (minimum-on-time) function to ensure reliable operation over a wide range of switching frequencies. The cycle-by-cycle MOT protection circuit automatically detects a light or no-load condition so that gate drives can be disabled to avoid unwanted reverse currents flowing through the MOSFETs. The IR1161L operates at a maximum switching frequency of 500kHz, and the IR11688S operates up to 400kHz.
Both the IR11611L and IR11688S controllers are in volume production.