A flow control device , comprising: a housing , a valve body assembly and a drive control component , wherein the housing comprises a first port and a second port ; the valve body assembly is partially received in the housing and comprises at least a movable valve member and a transmission part , the movable valve member is connected to the transmission part in a position-limited manner, and the movable valve member is movably arranged relative to the housing ; and the drive control component comprises a control unit , a power output unit , a magnetic element and a detection element , wherein the power output unit is connected to the transmission part in a position-limited manner, the power output unit provides a driving force for the transmission part and the movable valve member , the detection element is electrically connected with the control unit , the magnetic element is assembled with the power output unit and is fixed relative to the power output unit , a sensing part of the detection element is located within a magnetic field of the magnetic element and is arranged opposite to an outer periphery of the magnetic element , and a magnetic pole change generated by rotation of the magnetic element is sensed by the detection element ; the drive control component comprises a printed circuit board , the detection element and the control unit are secured to the printed circuit board by welding, wherein the printed circuit board comprises a main body base and an overhanging portion , where the overhanging portion protrudes from one end of the main body base and is overhung, characterised in that the detection element is assembled on one side of the overhanging portion by welding and is disposed facing the magnetic element , the housing comprises first positioning protrusions and a second positioning protrusion , the first positioning protrusions are located on both sides of the overhanging portion , and the second positioning protrusion is assembled with the main body base of the printed circuit board . the housing comprises a first port and a second port ; the valve body assembly is partially received in the housing and comprises at least a movable valve member and a transmission part , the movable valve member is connected to the transmission part in a position-limited manner, and the movable valve member is movably arranged relative to the housing ; and the drive control component comprises a control unit , a power output unit , a magnetic element and a detection element , wherein the power output unit is connected to the transmission part in a position-limited manner, the power output unit provides a driving force for the transmission part and the movable valve member , the detection element is electrically connected with the control unit , the magnetic element is assembled with the power output unit and is fixed relative to the power output unit , a sensing part of the detection element is located within a magnetic field of the magnetic element and is arranged opposite to an outer periphery of the magnetic element , and a magnetic pole change generated by rotation of the magnetic element is sensed by the detection element ; the drive control component comprises a printed circuit board , the detection element and the control unit are secured to the printed circuit board by welding, wherein the printed circuit board comprises a main body base and an overhanging portion , where the overhanging portion protrudes from one end of the main body base and is overhung, characterised in that the detection element is assembled on one side of the overhanging portion by welding and is disposed facing the magnetic element , the housing comprises first positioning protrusions and a second positioning protrusion , the first positioning protrusions are located on both sides of the overhanging portion , and the second positioning protrusion is assembled with the main body base of the printed circuit board . <EOS>