Electrotechnics Volume II self study notes 1.23

Non exam preparation materials
1.23

Chapter 18 DC regulated power supply

In industrial and agricultural production and scientific experiments , Mainly AC , But in electrolysis 、 electroplate 、 Battery charging 、 DC motor and other occasions , All need DC power . Therefore, the semiconductor DC regulated power supply , Turn the AC voltage into a stable and appropriate DC voltage .

It is divided into ： Rectifier transformer （ Convert the AC power supply voltage into a voltage that meets the needs of rectification , step-down / Isolation ）, Rectifier circuit （ Convert AC voltage into unidirectional pulsating voltage ）, filter （ Reduce the pulsation degree of rectifier voltage , Peak shaving and valley filling ）, Voltage stabilizing link （ When the AC power supply voltage fluctuates or the load changes , Keep the DC output voltage stable ）.

Rectifier circuit ： Half wave （ The negative half cycle is added to the diode ）、 Full wave （ Bridge ）、 Three phase bridge （ Triangle connection and star connection , It has large rectification power ）

filter ： Capacitive filter 、 Inductance capacitance filter 、π Shape filter （ The best effect , The cost is the highest ）

DC regulated power supply （ The core ）： Zener diode （ Match with suitable resistance ）、 Series voltage stabilizing circuit （ Series voltage negative feedback ）、 Integrated regulated power supply （ Three terminal integrated voltage regulator 、1 Input 1 Output 1 public ）.

That's all for analog circuits , Next, I will begin to study digital circuits in the next semester . Start today .

Chapter 20 Gate circuits and combinational logic circuits

electronic computer 、 Digital instrument 、 Digital communication and various digital control devices are based on digital circuits .
application ：
1. Taxi meter ： The source of the signal ： The pulse signal on the axle after shaping . digital circuit ： Counter （ Receive pulse signal ）、 Calculator （ Calculate the price ）、 Memory （ Store driving information ）、 Decoder （ Translated into decimal numbers ）、 Monitor （ According to the price ）.
2. Motor speed measuring system ： The source of the signal ： The light source passes through the small hole on the rotating motor , Converted into electrical signals by photoelectric elements . digital circuit ： Amplification circuit （ Amplify photoelectric signal ）、 Shaping circuit （ Easy to measure ）、 Gate circuit （ Whether the control signal passes ）、 Standard time generating circuit （ Control the opening and closing time of the gate circuit ）、 Counter 、 Decoding shows .