Briefly speaking, the controller is composed of peripheral devices and the main chip (or single-chip microcomputer). The design quality and characteristics of the controller, the function of the microprocessor used, the power switch device circuit and the layout of peripheral devices, etc., are directly related to the performance and operating status of the vehicle, and also affect the performance and efficiency of the controller itself. Different quality controllers, used in the same car, equipped with the same set of batteries in the same charge and discharge state, sometimes show a big difference in continued driving ability. Peripheral devices are some functional devices, such as execution, sampling, etc. They are resistors, sensors, bridge switch circuits, and devices that assist single-chip microcomputers or application-specific integrated circuits to complete the control process; single-chip microcomputers are also called microcontrollers, which are integrated on an integrated chip. Memory, decoder with signal language conversion, sawtooth wave generator and pulse width modulation function circuit, as well as the power tube of the switching circuit can be turned on or off, and the on time of the power tube can be controlled by the square wave to control the motor speed The drive circuit, input and output ports, etc. are integrated together to form a computer chip. This is the intelligent controller for electric bicycles. It is a high-tech product that appears as a 'fool'. Controller type At present, the principle of the controller circuit adopted by electric bicycles is basically the same or similar. Most of the brushed and brushless DC motors adopt the PWM control method of pulse width modulation to adjust the speed, but the selection of driving circuit, integrated circuit, switching circuit power transistor and some related functions are different. The difference in components and circuits constitutes the difference in the performance of the controller. There are two types of controllers in terms of structure. We call them separate and integral types. Separate The so-called separation means that the controller main body and the display part are separated and the latter is installed on the handlebar, and the controller main body is hidden in the car body box or electric box, not exposed to the outside. This method shortens the connection distance between the controller, the power supply and the motor, and the appearance of the car body is simple. The box is installed in the middle of the handlebar, and the panel of the box has a small number of small holes with a diameter of 4~5mm, and a transparent waterproof membrane is applied on the outside. The corresponding position in the hole is equipped with light-emitting diodes to indicate the vehicle speed, power supply and remaining battery power. The integrated control part is integrated with the display part and is housed in an exquisite special plastic box.