If there is a more thorough solution, I will choose to wait, can not give in to the subtle penetration of life, you can not guarantee that the gentle temptation, will not hide the howl of rage, more can not ignore the time of the insult.
Regulator tube is a kind of existence is very distinctive, contrasts its forward and reverse features, an experienced engineers can according to the characteristics of its ingenious design of the circuit, solve the problems faced in the practical, here I'll use stabilivolt an article to tell you about the features, selection and application of the aspects of content.
1 Definition of regulator tube
The regulator diode, also known as the Zener diode, is a silicon material made of surface contact type crystal diode, referred to as the regulator tube. The forward guide has a junction voltage equivalent to that of a conventional diode (0.3-0.7V), and the reverse guide stabilizes around a value over a range of varying currents.
The voltage regulator provides a stable voltage through an inverse guide, but the stable voltage is affected by temperature, current and other factors.
2 classification of voltage stabilizing tubes
1) Classification by material
Plastic packaging
The stabilized tube of plastic package is divided into surface package and lead package.
Metal package
Glass package
2) According to whether there is temperature compensation classification
Ordinary regulator tube
(2) the regulator tube with temperature compensation
The regulator tube with temperature compensation has a certain self-regulation ability when the temperature changes, so that the voltage temperature is added in the regulator value.
3) Classification by power
The power is divided into three types according to the current capacity of the regulator tube.
Small power regulator tube
Medium power regulator tube
High-power regulator tube
Common nominal voltage of the regulator tube
The nominal value of the common regulator tube is as follows.
3.3V 3.6V 3.9V 4.7V 5.5V 5.6V 6.2V 15V 27V 30V 75V, etc.
Volt-ampere characteristics of the regulator tube
The voltage-ampere characteristics of the regulator tube are as follows, taking UDZS6 series for example.
Each line in the figure above is a type of regulator tube with current on the vertical axis and voltage on the horizontal axis.
It can be seen that the voltage of this series of regulator tube is relatively stable in the current range from 100nA to 1mA, and there are some differences in the voltage variation after 1mA.
It can be seen that the regulator characteristics of the regulator tube with a nominal value lower than 5V are worse.
Common parameters of the regulator tube
The abbreviations mentioned below are commonly used in the regulator manual. If you need to check the parameters of the model regulator, you can find them according to the abbreviations.
1) Stable voltage (Vz)
The stable voltage generated at both ends of the regulator when it operates at rated current. This value will vary slightly with current and temperature (within a certain range).
2) Stable current (Iz)
The reverse current flowing through the regulator when a steady voltage is generated. The stable current Iz has a limited range of minimum and maximum stable currents.
3) Reverse leakage current (IR)
The leakage current generated by a regulator diode at a specified reverse voltage. Generally speaking, smaller leakage current is better, but it depends on the situation. Moreover, if leakage current affects the characteristics of other parts of the current, smaller leakage current is not necessarily better.
The leakage current of the regulator tube will be different at different voltages, which can be generally found in the manual.
4) Dynamic resistance (RZ)
The ratio of the voltage change at both ends of the regulator tube to the current change. Because the voltage is documented, this value is affected by the current and is inversely proportional to the current.
5) Dissipation power (Pz)
The power consumption generated when the reverse current passes through the PN junction of the regulator tube. The PN junction is affected by temperature, so the power consumption of the regulator tube is determined by the temperature characteristic of the PN junction of the regulator tube.
Pz = stable voltage (Vz)* Maximum allowable current (Izm).
6) Temperature coefficient (Ctv)
The variation coefficient of the voltage of the regulator tube under the influence of temperature. It is the percentage change in voltage for every 1 degree increase in temperature.
6. Application scenario of the regulator tube
The role of the regulator tube is to stabilize the pressure, but it is not so simple, because there are different scenes, so the role of the regulator is different.
According to the form of regulator tube in the circuit can be divided into series regulator circuit and parallel regulator circuit.
Series voltage regulator circuit:
Series regulator tube is generally used to stabilize the pressure of the regulator tube, of course, it is mainly suitable for the regulator scene.
Parallel voltage regulator circuit:
The regulator diode is parallel to the output end, the voltage on the regulator tube is the output voltage. This kind of parallel connection is mainly used in the situation where the input voltage changes little and the load current is small.
In parallel with the protection circuit, to protect the important circuit role, you can refer to the following single protection circuit.
The regulator tube has the following several application scenarios.
1) Provide stable voltage for the circuit
This regulator tube is the most essential function. However, it should be noted that the voltage regulation accuracy of the regulator tube is different, depending on the model and the precision of the regulator tube. In most cases, it is not possible to use the stabilized voltage tube as the stable voltage, and the stabilized voltage value will change after the aging of the stabilized voltage tube.
2) Overvoltage protection
One application scenario is that when the circuit exceeds a certain voltage, the voltage regulator is earthed and the voltage is pulled down.
3) Surge protection
When there is surge input, one way is to release the surge to the ground, the other way is to separate the load and so on from the power supply through the regulating tube conduction relay.
4) Arc suppression
If a suitable voltage regulator diode (or an ordinary diode can be connected in parallel) is connected to the inductance coil, when the coil is cut off in the conduction state, the high voltage generated by its electromagnetic energy release will be absorbed by the diode, so when the switch is off, the arc of the switch will also be eliminated. This application circuit is widely used in industry.
5) Single protection circuit
Under certain circumstances, the regulator tube is used as a protective device. When a large voltage comes in, the regulator tube is broken down to short-circuit other circuits to be protected. This would be at the expense of the regulator, so it's a single protection, a little bit of insurance.
6) Used as rectifier diode
The rectifying diode of the stabilizer tube has a limitation that the finishing output voltage is less than that of the stabilizer tube.
7 summary
Above from the nominal value of voltage regulator tube, characteristics, classification and parameters, application scenarios are introduced, which includes such aspects as everyone through the understanding of these aspects, can grasp the situation of voltage regulator tube used, here only did some ChongDianXing understanding, not combined with the circuit analysis, we can go online to find related circuit, if you want to know a more in-depth content stabilivolt, went to see the models used manual voltage regulator tube!
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