Schematic diagram of miner switch power supply
This is the electrical schematic diagram of QBZ-80 switch. If you want to connect the start button and stop button, connect the start button to line 1 and line 2, and the stop button to line 2 and line 9. If there is no need for external control, just short circuit 2 and 9 wires directly and use the button of the switch itself to control the start and stop. Hope to help you
who can give a simple circuit diagram of switching power supply with principle explanation., It's so hard. I've worked hard to answer. Give me a satisfactory answer
The switching power supply mainly consists of three parts: PWM control mole, switch tube (BJT, MOSFET, IGBT, etc.) and filter (inctor, capacitor). The isolating switching power supply also includes isolating transformer. Of course, we should also consider the design of EMI, PFC (power factor correction)
there are some linear power supplies in the low power supply, but in the medium and high power supply, the linear power supply has been replaced by the switching power supply. With the improvement of frequency and function of control chip, the development of high-speed and low-power power switch transistor is successful, switching power supply is the main development direction of power supply in the future
extended data:
precautions:
1. The input voltage of switching power supply can be 220 V or 110 V, and the input voltage gear should be selected reasonably according to the circuit design. Otherwise, the switching power supply will be damaged
Pay attention to distinguish the ground terminal and zero terminal of the output voltage terminal of switching power supply. And ensure that the switching power supply is grounded reliably3. The metal shell of switching power supply is generally connected to the ground (FG), which should be reliably grounded to ensure safety, and the shell should not be connected to the zero line by mistake
In order to achieve sufficient heat dissipation, the general switching power supply should be installed in the position with good air convection conditions, or installed on the chassis shell, through which the heat is transmitted to the outside Before leaving the factory, the switching power supply should be tested with resistive load. If it needs capacitive or inctive load, it should be explained in the order contract in advance1、 Switching power supply working principle
1, switching power supply connected to the control mode is divided into two types of width molation and frequency molation, in practical applications, the width molation is used more, in the current development and use of switching power supply IC, the vast majority is also pulse width molation. Therefore, the following is mainly about the width adjustable switching power supply
2. Refer to the figure below for the basic principle of width adjustable switching power supply
1. Switching power supply connected to control mode is divided into two types: width molation type and frequency molation type. In practical application, the width molation type is widely used, and in the current development and use of switching power supply IC, the vast majority is also pulse width molation type. Therefore, the following is mainly about the width adjustable switching power supply
2. See the figure below for the basic principle of width adjustable switching power supply
3. For monopolar rectangular pulse, the average DC voltage uo depends on the width of the rectangular pulse. The wider the pulse is, the higher the average DC voltage is. Average DC voltage U. It can be calculated by the formula, that is, uo = um × In T1 / T, um is the maximum voltage of rectangular pulse; T is the period of rectangular pulse; T1 is the rectangular pulse width
4. It can be seen from the above formula that when um and T are constant, the average DC voltage uo will be proportional to the pulse width T1. In this way, as long as we try to narrow the pulse width with the increase of the output voltage of the regulated power supply, we can achieve the purpose of stabilizing the voltage< Second, the principle circuit of the switching mode power supply
basic circuit
supplement:
1. The AC voltage is rectified and filtered by the rectifier circuit and filter circuit, and then becomes the DC voltage with a certain pulsating component, which is converted into the square wave of the required voltage value by the high frequency converter, and finally becomes the required DC voltage by the rectifier filter< The control circuit is a pulse width molator, which is mainly composed of sampler, comparator, oscillator, pulse width molation and reference voltage. At present, this part of the circuit has been integrated into a variety of integrated circuits for switching power supply. The control circuit is used to adjust the switching time ratio of high frequency switching elements to achieve the purpose of stabilizing the output voltage.
Found on the Internet,
Switching power supply is a kind of power supply which uses modern power electronic technology to control the time ratio of switching transistor on and off and maintain stable output voltage. The simple structure is shown in Figure 2-1
Figure 2-1 basic circuit of switching power supply the switching transistor VT is connected in series between the input voltage VI and the output voltage Vo. When the base of the transistor VT inputs the switching pulse signal, the VT is switched periodically, that is, alternately in saturated on and off. Assuming that VT is an ideal switch, the base of VT turns on at saturation. The voltage drop between the emitters is approximately zero, and the input voltage VI is applied to the output through vt; On the contrary, ring the VT cut-off period, the output is zero. The average DC voltage of VT can be obtained by filtering circuit.
1、 The basic working principle of switching mode power supply is divided into two types: width molation and frequency molation. In practical application, the width molation is widely used. In the current development and use of switching power supply IC, the vast majority of them are pulse width molation. Therefore, the following is mainly about the width adjustable switching power supply
the basic principle of width adjustable switching power supply can be seen in the figure below
turn left | turn right