Flyback Converter Controller Timing-Based Output Power Measurement

The patent extracts the measurement function from complex peak detection and sample-hold circuits to a simplified sampling circuit that takes measurements at specific timing points during the switching cycle. By measuring at the valley point (when current is minimum) and using timing-based sampling, the patent eliminates the need for complex peak detection circuitry while improving accuracy by avoiding leading edge spikes.

The patent performs preliminary sampling of the current sense signal at predetermined timing points (valley point and specific phase points) before the switching cycle completes. This preliminary action allows the system to capture accurate current values without waiting for peak detection, thereby avoiding delays and improving measurement responsiveness.

The patent converts the harmful leading edge spike into a useful timing reference. By identifying the valley point (minimum current point) and using it as a reference for subsequent measurements, the system transforms the problematic spike region into a beneficial synchronization point that enables accurate measurement of the continuous current component that would otherwise be obscured.

The patent employs dynamic timing-based measurement where the sampling points are positioned at specific phases of the switching cycle rather than at fixed time intervals. This dynamic approach allows measurements to be taken at optimal moments (valley point, turn-on phase points) that capture the continuous current information while naturally filtering out the transient leading edge spike effects.