Switching-Mode Power Supply Control Circuit for Fast Transient Response

The patent applies dynamics by transitioning from fixed frequency control to variable frequency control. The control circuit dynamically adjusts the switching frequency based on transient conditions: during normal operation, a fixed frequency maintains stability; during transient events (load changes, startup), the frequency varies to optimize response. This is achieved through detecting transient states and adjusting the clock signal frequency accordingly, allowing the system to adapt between stability and speed requirements.

The patent uses periodic action by implementing multiple switching cycles within a single clock period during transient conditions. Instead of being limited to one switch-on event per clock cycle, the control circuit enables continuous or repeated switching actions until the transient condition resolves. This allows the main MOS to remain effectively on for longer durations by resetting the switch-on condition in successive cycles, overcoming the fixed clock cycle time limitation while maintaining precise timing control.

The patent applies feedback by implementing a control circuit that continuously monitors both the output voltage and inductor current. The control circuit uses this feedback information to make real-time adjustments to the switching timing and duration. When output voltage drops are detected, the circuit extends turn-on time while simultaneously monitoring inductor current to prevent overshoot. The feedback mechanism allows the system to balance voltage stability and current control by adjusting switching parameters based on actual circuit conditions rather than fixed timing.

The patent applies parameter changes by modifying the clock signal frequency parameter dynamically based on circuit conditions. During normal operation, the clock frequency remains at a standard value for simple control. During transient events (load changes, startup, shutdown), the control circuit detects these conditions and adjusts the clock frequency to higher or lower values to optimize the switching timing and response speed. This parameter adjustment allows rapid response to load changes while maintaining circuit simplicity through a unified control approach that adapts to different operating conditions.