摘要:
Provided are a light-emitting diode driver circuit and an LED light source which are capable of reliably turning OFF an LED even when an input voltage having a value smaller than a predetermined value is supplied. A light-emitting diode driver circuit (1) for turning ON an LED (2) includes: an inverter (20) which outputs electric power for driving the LED (2); and an inverter control circuit (30) which controls an operation of the inverter (20), and when a DC voltage applied to the inverter control circuit (30) has a value smaller than the predetermined value, the inverter control circuit (30) stops the operation of the inverter (20).