DC-DC Converter Midpoint Coil Current Sampling for Stable Control

The patent applies preliminary action by generating a timing control signal in advance that specifies the exact midpoint timing for current sampling. This timing signal is prepared before the switching cycle executes, ensuring that coil current is sampled precisely at the midpoint of ON or OFF periods. By pre-establishing the sampling timing rather than using conventional peak or bottom value detection, the system maintains stable average coil current independent of input and output conditions, thereby improving overcurrent protection reliability.

The patent implements feedback by sampling the coil current at the midpoint of ON or OFF periods and using this sampled value for output feedback control. The timing control unit generates precise timing signals to ensure midpoint sampling, and the control circuit adjusts the switching output stage based on the feedback from this stable current sample. This feedback mechanism maintains consistent average coil current across varying input and output conditions, significantly improving light load detection operation reliability without requiring overly complex circuitry.

The patent applies dynamics by making the current sampling timing adaptive to the switching cycle phase rather than fixed at peak or bottom values. The timing control unit dynamically generates timing signals that correspond to the midpoint of ON or OFF periods, which changes with each switching cycle. This dynamic timing adjustment ensures that sampling always occurs at the correct midpoint regardless of input voltage or load conditions, maintaining stable average coil current while keeping the implementation relatively simple through systematic timing control.