This design for the pressure measurement and control device, application of pure hardware circuit, through the comparison of the current pressure value and set pressure value to automatically control the output.
Control part of the application of combinational logic circuit, simple structure, stable performance.
Of sensing application classical sensor circuit, bias current is small, small disturbance, high gain, common mode rejection capability, fast response, low drift, stable performance, low price.
The output part adopts photoelectric coupling to prevent interference caused by high pressure.
Using digital tube as a display part of the system, its small size, power consumption, fast response, easy to match, high reliability and long service life.
Advantage is that the system speed, strong anti-jamming capability, high reliability.
The pressure measurement and control instrument high practical value, implement for more than a table in a controlled way, according to reduce the usage of mechanical watch, not only reduces the cost of production equipment, at the same time ensure the consistency of the production process, make the production efficiency and product quality has been improved greatly.
Key words: automatic control logic circuit sensor Abstract The design topic of this subject is a instrument of The pressure measures and control, applied pure hardware electric circuit, which compare The current pressure value with set up The pressure value to auto -
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The control logic circuit sensor to record the preface 5 1, brief 6 2, design thinking 3 July 3, main circuit design principle and calculation.
1, sensors, choose 3 July.
1 and correct selection of the sensor principle 7. 3.
2, sensors, signal processing and amplification circuit 11 3.
2, the output control 12 3.
1, select relay 14 3.
3, 16 3 channel selection.
4, according to some 25 3.
5, power supply section 25 3.
6, choice of transformer 27 3.
7, introduction of assembly figure 28 4, circuit board 29 April.
1, the general principles of the circuit board design April 29.
1, the selection of circuit board 4 29.
2, the size of the circuit board 29 April.
3, 30 4 layout.
4, wiring and 4.
31 4 5, welding plate.
32 4 6, large area filling.
2, grounding 32 4.
1, the total impedance of interference of ground 32 4.
2, any ground connection 33 4.
3, 33 anti-interference design 4.
1, to increase the system ability to resist electromagnetic interference should take some measures