Composite intrinsic safety circuit

The utility model discloses a composite intrinsically safe circuit which comprises an input end, an LED light source unit, an LDO power supply and protection unit, an MCU control unit, a key unit, an MOS tube unit and a current-limiting resistor unit, and the current-limiting resistor unit comprises at least one group of resistor modules formed by connecting a plurality of resistors in parallel. And the resistor module is connected in series between the MOS tube unit and the LED light source unit. The LED lamp is reasonable in structural layout, a main loop is formed by the MOS tube unit, the current-limiting resistor unit and the LED light source unit, the current-limiting resistor unit comprises one or more groups of resistor modules formed by connecting a plurality of resistors in parallel, and the working current of the LED light source unit is limited through the resistors in the resistor modules, so that the working efficiency of the LED lamp is improved. Therefore, the current requirement of a short-ci