Semiconductor laser adjustable constant current driving circuit based on three-section voltage stabilizer

The invention relates to an adjustable constant current driving circuit, in particular to a semiconductor laser adjustable constant current driving circuit based on a three-section voltage stabilizer,and belongs to the technical field of laser control. The adjustable constant current driving circuit comprises an operational amplifier U10, an MOS (metal oxide semiconductor) transistor Q19 and a laser LD which are connected sequentially, wherein a forward input end of the operational amplifier U10 is connected with a power input end through a resistor R3, two ends of the resistor R3 are connected in parallel with an NTC thermistor R2 with a negative temperature coefficient, and the thermistor R2 is located on a cooling housing of the laser LD. Therefore, the adjustable constant current driving circuit has the advantages as follows: 1, instability of laser output due to temperature factors in a conventional constant temperature manner is relieved; 2, the circuit is simple in structure and completely practical. 本