LED DIMMING CIRCUIT

摘要

PURPOSE: An LED dimming circuit is provided to control LED blinking by controlling on/off of a control transistor based on a DC voltage in which a pulse is changed for dimming control. CONSTITUTION: A triac(triode AC switch) dimmer(12) generates a triac pulse. A full wave rectifier circuit(14) full-wave-rectifies the triac pulse from the triac dimmer. A control transistor(20) turns on and off of a driving current flowing in an LED. A comparison circuit(26) compares a driving current value and a designated value detected by a current detecting circuit. A conversion circuit changes the triac pulse into a DC voltage signal. [Reference numerals] (12) Triac dimmer; (AA) Control signal; (BB) Trigger pulse