CONSTANT CURRENT TYPE LIGHT EMITTING DIODE LIGHTING CIRCUIT

摘要

A constant current type LED lighting circuit is provided to prevent voltage resonance or current resonance by controlling a voltage and a current at the same time. A current detection control part(70) detects and controls a current flowing to an LED module(60) through a current monitor(71) and a first photocoupler(72). A voltage detection control part(80) detects and controls a voltage of both ends of the LED module through a second photocoupler(81). A calculation control part(90) controls a detection value of the current detection control part and the voltage detection control part at the same time. A detection current stabilizing part(100) includes an R25 resistor and an R15 resistor. The R25 resistor detects abnormality of a current. The R15 resistor delivers a detection value of the R25 resistor to a C13 condenser.