3 What is the maximum voltage of a 6V Zener diode

Since it is a regulator diode, it is stable.

Of course, you can't directly power it, otherwise don't talk about it, even if it is, it may burn.

If it's a power supply, add a 200 ohm resistor.

Diodes, pn junction type, must be limited current things, and must not be directly connected to the power supply. Current is usually limited with resistors.

The voltage after the breakdown of the regulator tube is the nominal voltage regulation value. Its voltage has nothing to do with the power supply voltage, it is a fixed voltage stabilization value, and the excess voltage falls on the current limiting resistor, so it must be limited current resistor.

The formula for calculating the current limiting resistor:

Power supply voltage (nominal regulated value) Stable current (take 10mA).

Generally, the stable current is about 10mA, as you said (ohm. If 1k, (, the current is too small, and the regulator tube will not work.

I don't know what you are using it for, the stable current of the regulator tube is very small, generally only a few tens of milliamperes, and its use is mainly used as a reference voltage. It is not used for direct power supply.

Depending on your use case, combined with the specific circuit, do not exceed the maximum stable current, different types of diodes have different maximum voltage stabilization currents, the specific value can refer to the diode manual, or it.

I'm an electronics amateur, purely theoretical, and have a limited knowledge of specific components, so I hope it can help you.

linhuguang888 is right, the function of the regulator tube is to stabilize the voltage, plus the excess voltage will stabilize the voltage on the left and right, but it cannot be directly connected to the power output, and the current resistance must be limited in the middle.

Whether the regulator tube will be broken or not depends on how much power you choose, that is, through the product of the power supply and stable voltage of the regulator tube, it will be damaged if it exceeds the limit. Generally, a voltage regulator tube can be stabilized by a few milliamperes. Therefore, the input voltage, current limiting resistor, you can choose 200 ohms, 1k is a bit big, the current is too small is not conducive to the stability of the voltage regulation.

You can look at the parameters of the current, generally there will be a typical value, the minimum value, the maximum value, do not exceed the maximum value. The higher the current, the more the device heats up, and the stabilized voltage may be slightly higher.

The overpressure use of diodes should generally not exceed 10%.

There is no limit to the maximum voltage, as long as the current limiting resistance is calculated when the circuit is designed.

，。The stable voltage uz uz is the breakdown voltage of the PN junction, which varies slightly with the operating current and temperature. For the same type of regulator tube, the voltage regulation value has a certain discreteness. Stable current iz The reference current value of the regulator tube when it works, usually has a certain range, i.e., izmin - izmax.

The dynamic resistance is the ratio of the voltage change at both ends of the regulator tube to the current change, that is, this value changes with the difference of the working current. In general, the higher the operating current, the smaller the dynamic resistance, and the better the voltage regulation.

You flip through the book to see what the principle of this regulator is, with all due respect, you are simply not a difficult problem, the Zener diode belongs to the period of parallel voltage stabilization, as long as the reverse diode series resistance, do not exceed the power consumption of the regulator tube, work in the reverse breakdown area of the Zener diode, the two ends of the diode are but due to the existence of on-resistance, there will actually be a difference of more than a dozen millivolts, of course, the larger the current The greater the dissipation of the tube, the voltage will rise a little bit, and it may be, Generally speaking, if the requirements are not high, just use this, and, if you need tight voltage regulation, it is recommended that you use LM339, TL431, absolutely accurate, plus a negative compensation, you can make 5 24V change of power supply voltage, there will only be a difference of 1MV, you look at the above two chips You will understand all of them. Hope it helps!!

The voltage regulator tube only has a nominal stable voltage index, and there is no maximum voltage index.

The limiting parameter of the regulator tube is the maximum power dissipation, for example, the small power regulator tube with glass seal is 1 2W, and the maximum allowable current can be converted from the voltage regulation value.

It can be understood as: the maximum input voltage value of the Zener diode is twice the rated voltage value of the Zener diode, if it is, if the input voltage is higher, it is easy to burn out, if it is too low, plus the VF value of the Zener Diode may be lower than the rated value of the Zener Voltage, then it can no longer play the voltage stabilization effect that it should have.

IN4728 Zener Diode 1mA Motorola 1W Series.

Maximum current IM = 270mA

This is because many devices are powered by 5V. Some devices have high requirements for voltage, requiring the ripple of the power supply voltage to fluctuate in a small range (such as tens of mV) to work normally, in this case, the voltage regulator device is required to stabilize the voltage within a certain range to ensure the normal operation of the circuit.

Moreover, there is no "maximum input voltage" for the regulator, only the maximum input current parameter. The purpose of the two is the same, both are used for voltage stabilization, the difference is that the three-pole regulator tube is used for high-current regulation, and the two-pole regulator tube is used for low-current regulation.

For example, the maximum current of the regulator tube is 200mA, with 100 current limiting resistors, the differential voltage δu=100*, and the input voltage u==. Beyond it, the regulator tube will burn out.

The regulator diode is not necessarily yes, but also 14V ah, etc., it is mainly to protect the circuit from being burned out by large currents.

The stable voltage is.

There are also many other nominal ones, 12v....

It is indeed so small, the commonly used red kind is 20--30ma, imported off-white (a little larger) 50--60ma, 2w is not clear, anyway, it will not exceed 80ma, it is impossible to directly use the voltage stabilizer tube to stabilize the voltage.

The current value you understand should be correct, otherwise it will not match its nominal power.

Of course, it's the 166ma you said. The manufacturer is talking nonsense and scolding him!

MultiSim's diode library "Diodes" The "Zaner" sub-library is a regulator diode library, which contains multiple regulators with different power ratings.

In the "Select a Compleenent" small window, select a component model, and then click the 4th button "Detail Report" in the upper right part of the window to query the specific parameters of the component. For example, the 1N5233B has a regulated voltage value, a minimum stable operating current, and a rated power consumption of 6V, 20mA, and 6V, respectively.

There are also some tubes that directly contain the voltage regulation value data, such as 4V7 and 4V7 both indicate that the voltage regulation value is, you can enter "*4V7" in the "CompleNent Component" box (there must be an * sign before the data), and you can list all the models that include 4V7 in the model.

Note: The voltage stabilization value of the voltage regulator tube mostly adopts the E24 series value of the resistor-capacitance element, and the voltage stabilization value higher than 3V and lower than 10V is often not an integer value, such as 6V is less but more.

Zener diode, English name zener diode, also known as Zener diode. This is a voltage regulator diode that uses the phenomenon that the current can change over a wide range while the voltage remains basically unchanged in the reverse breakdown state of the PN junction. [1] This diode is a semiconductor device that has a very high resistance until the critical reverse breakdown voltage.

At this critical breakdown point, the reverse resistance is reduced to a small value, in which the current increases while the voltage remains constant in the low-impedance region, and the Zener diode is binned according to the breakdown voltage, which is mainly used as a voltage regulator or voltage reference element. Zener diodes can be connected in series for use at higher voltages, and higher stable voltages can be obtained by connecting them in series.

The input reverse voltage of the Zener diode must be greater than the Zener value to have a stabilizing effect.

For example, after the input voltage is 5% regulated diode, the output voltage will be stable and will not exceed its regulated value range due to the voltage fluctuation of the input voltage.

Depending on the voltage regulation, it can be subdivided into dozens of gears, such as 2V up to 200V...

The voltage range of each grade can be divided into 2% and 5% according to the production conditions and different processes (10%-15% when it was first produced 30 years ago).

For example, a commonly used 5% regulated value range is v-interval with a regulated effect.

But subdividing down to 2% can lead to ===

Of course, depending on the power level, it can also be divided.

There are many stabilizing values of the regulator tube, such as,,。 And so on, the circuit that requires a certain range of voltage stabilization value can choose a voltage regulator tube similar to the voltage stabilization value, such as power supply circuit, 12V circuit, can be stabilized with a voltage regulator tube between 11-13V, but if it is used as a reference voltage, it should be consistent with the parameters of the icon as much as possible, otherwise the relevant component parameters should be adjusted, if the value of the voltage regulator at hand is higher than the requirements, the output voltage can be divided by a resistor or adjustable resistor, if it is a low required voltage, it may be connected in series through the voltage regulator tube, or in series with rectifier tubes of the IN series (each to achieve the required voltage regulation.

When it works normally, it works in the reverse breakdown state, and the negative pole can only work when the positive power supply is connected.

1. When UI=10V, assuming that the regulator tube can stabilize the voltage, then, the voltage drop above the UO=WZ=Ω resistor is 10-6=4V, and the current flowing through this resistor is 4 1000=4mA. Even without considering the shunt of the load resistance, the regulator tube can only flow through 4mA current, and this current is not enough to open the regulator tube, and the regulator tube cannot stabilize the voltage, so it is in the cut-off state. At this time, the regulator can be regarded as an open circuit, UO is the voltage division of 500 ohm resistance and 1k ohm resistance to 10V, and the output value is.

2. When UI=15V, assuming that the regulator tube can stabilize the voltage, then, the voltage drop above the UO=WZ=Ω resistance is 15-6=9V, and the current flowing through this resistor is 9 1000=9mA. If the shunt of the load resistance is not taken into account, this current is between IZ Min and IZ Max, and the regulator should be able to break down (Zener breakdown) regulation. However, when considering the load, is this current sufficient to open the regulator?

Through the following calculations, I found that the answer to the original question was wrong!

In fact, this problem should be solved by the open path method. It is assumed that the regulator tube is open, first calculate the value of UO, if it is greater than the regulator value, and then consider whether the current value in the circuit meets the working conditions of the regulator tube in the regulated state.

UI=15V, the voltage division of 500 ohm resistance and 1k ohm resistance to 15V, the voltage division on the 500 ohm resistance is 5V, obviously, this voltage value is lower than the rated voltage stabilization value of the 6V regulator tube, and the voltage regulator tube should not break down and stabilize! Conditionally, it is possible to lap a component to a circuit for actual testing.

3. When UI=35V, if the load is open, assuming that the regulator tube breaks down and conducts on, the voltage can be stabilized at 6V, then the current above the 1K ohm resistance is (35-6) 1000=29mA, which has exceeded the maximum stability value of the regulator tube of 25mA, and the regulator tube will be broken down by avalanche, resulting in irreversible damage.

To sum up, when the parameters do not change, we can further calculate the UI range when the regulator tube can be regulated:

iz min=5mA uz=6v,il=12mA,i total=5+12=17mA,1k ohm resistor drop is 17V,ui=17+6=23V!

iz max=25mA uz=6v, IL=12mA, i total=25+12=37mA, 1k ohm resistor drop is 37V, UI=37+6=43V!

The range of the UI is 23V--43V. If you consider the possible open-circuit scenario of the load, UI max=25V.