Defense of DC regulated power supply: Part I: Firstly, the design task, functional requirements and overall scheme are introduced; *; 1. Design and manufacture continuously adjustable DC regulated power supply. The main technical indicators are as follows: ① adjustable output voltage: UO =+3V ~+9V ② maximum output current: Iomax=800mA ③ output voltage change: δ UO ≤ 15MV ④ regulation coefficient: SV≤0.003.
2. Design the circuit structure, select the circuit components, calculate and determine the parameters of the components, and draw a practical principle circuit diagram.
3. Draw up the test methods, procedures and data sheets, and put forward the specifications and quantities of instruments and components required for the test.
4. Assemble and debug in the laboratory, and test its main performance parameters. ; 1, circuit diagram design
(1) Determine the goal: design the whole system composed of those modules, signal transmission between modules, and draw the block diagram of DC regulated power supply.
(2) System analysis: According to the system function, select the circuit form used by each module.
(3) Parameter selection: according to the system index requirements, determine the parameters of components in each module circuit.
(4) General circuit diagram: connecting the circuits of each module.
2. Circuit installation and debugging
(1) In order to improve the practical ability, the printed circuit board is designed and soldered.
(2) Add a signal to the input of each module circuit, test the output signal, and verify whether each module can reach the specified index.
(3) Focus on testing the voltage stabilizing coefficient of the voltage stabilizing circuit.
(4) Connect the circuits of each module, debug the whole machine and measure the system indicators. ; Design idea of 1 DC regulated power supply
(1) The power supply voltage of the power grid is 220V (effective value) 50Hz. In order to obtain low-voltage DC output, a power transformer must be used to obtain the required alternating current.
(2) The stepped-down AC voltage becomes unidirectional DC through the rectifier circuit, but its amplitude changes greatly (that is, the pulse is large).
(3) The DC voltage with large pulsation must be changed into a smooth DC with small pulsation through a filter circuit, so as to filter out the AC component and keep the DC component.
(4) After the filtered DC voltage is stabilized by the voltage stabilizing circuit, a stable DC voltage output basically unaffected by the outside world can be obtained. ; 2.DC stabilized power supply principle DC stabilized power supply is a device that converts 220V power frequency alternating current into DC voltage and outputs it at a regulated voltage. It needs to go through four steps: transformation, rectification, filtering and voltage stabilization, as shown in figure 1.4. 1. ; The functions of each part of the circuit are as follows:
(1) electricity