PLANAR ILLUMINATING DEVICE AND DISPLAY DEVICE PROVIDED WITH SAME

摘要

A backlight device for adjusting the brightness by turning on/off a switch provided in parallel to each LED, wherein deterioration/damage of to the LEDs, variations in the brightness, and flickering are suppressed. The backlight device comprises an LED array (110) consisting of a plurality of LEDs (112) connected in series and bypass switches (transistors) (114) each provided in parallel to each of the LEDs (112), a bypass switch drive circuit (128) for switching between on and off of the bypass switches (114), an FET (122) having a drain terminal connected to the LED array (110) and a source terminal which is grounded, a constant-current drive control circuit (124) for supplying a constant-current to the LED array (110) by applying a predetermined voltage to the gate terminal of the FET (122), and a capacitor (126) one end of which is connected to the gate terminal of the FET (122) and the other end of which is grounded.