LED CURRENT CONTROL CIRCUIT

摘要

The present invention detects a current flowing through a bypass circuit and a constant current circuit by a single current detecting resistor. An LED current control circuit is characterized by comprising: a current limiting circuit (102) which limits an LED current flowing between current limiting circuit terminals; a bypass circuit (101) which limits a bypass current flowing between bypass circuit terminals connected between a first part LED row (13) and a second part LED row (14); and a current information detecting element (103) which is connected to the current limiting circuit output terminal and the bypass circuit output terminal, and characterized in that the current limiting circuit limits the LED current on the basis of current information detected by the current detecting element and a predetermined first coefficient, the bypass circuit limits the bypass current on the basis of the current information and a predetermined second coefficient according to the state of pulsating voltage to thereby control the current flowing to the current detecting element from the first part LED row through the bypass circuit such that the current flows to the second part LED row without passing through the bypass circuit.