20140191659 | LED LAMP CONTROL CIRCUIT - An LED lamp control circuit comprises a rectifier circuit, an LED light source load, a constant current circuit, and a first temperature detect switch circuit. The LED light source load comprises at least one group of LEDs. The constant current circuit comprises at least one group of constant current source components, each of which is connected to at least one group of LEDs in the LED light source load and comprises a depletion mode field effect transistor. The first temperature detect switch circuit is connected to an input end of a power source, and comprises a first normally closed temperature detect switch mounted on a radiator. When the temperature of the radiator exceeds the disconnection temperature of the first normally closed temperature detect switch, the first normally closed temperature detect switch is disconnected, so as to cut off the power supply of the LED light source load. | 07-10-2014 |