CIRCUIT FOR OUTPUT VOLTAGE ERROR CORRECTION IN SMPS WHICH REGULATION IS DONE BY PRIMARY SIDE CONTROL

摘要

The present invention relates to a constant- voltage error correction circuit for a primary regulation-type Switching Mode Power Supply (SMPS), which, in an inexpensive primary regulation-type SMPS, predicts variation in the load and corrects an output voltage in response to the predicted variation in the load. The constant- voltage error correction circuit for an SMPS, which has a magnetic energy transfer element, includes an error detection unit for receiving detection input voltage from the winding of the magnetic energy transfer element and reference voltage and detecting the errors of output voltage of the SMPS; a time constant unit for outputting the average value of error detection voltage output from the error detection unit; and a detection input control unit for varying the detection input voltage of the error detection unit in response to the average value output from the time constant unit.