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What are the whole bridge and rectifier diode?

Last Update Time: 2019-09-03 10:02:32

The whole bridge


Four-pins full bridge in the form of integration block; the other is the full bridge in the form of four diode.


For the full bridge with four pins, the two pins in the middle are AC input, the other pin with a missing corner is the positive pole, and the remaining one is the negative pole.. For full bridges in the form of four diode. Can use the multimeter diode block, one connects fire line or zero line, the other pen test 4 diode 8 pins, first find out its AC input pins (4), and then according to the direction of the diode, checked out the full bridge positive pole (2 pins), the remaining 2 pins is the full bridge negative pole.


In the maintenance of any power supply, the first  is to test  that is  it possible to connect directly between fire line and zero line of AC electricity 220V socket  . Its essential intention is to judge whether the whole bridge is damaged or not. However, the detection can only determine whether the diode in the whole bridge has reverse breakdown, and can not judge whether the tube in the whole bridge is forward open. Therefore, for the full bridge measurement, or according to the isolated diode measurement method, each measurement twice (positive deviation conduction, anti-bias cutoff), a total of 8 times to judge its good or bad by testing 8 times.


Type identification of rectifier diode.


In practice, we often need to know the specific parameters of the rectifier diode (including the full bridge), which can be learned by observing the surface model of the diode.


By looking at the data table of any rectifier transistor, it is not difficult to find that the tube actually has many electricity parameters, but the most important of them is only two: the maximum forward average rectified current (Maximum Average Forward Rectified), abbreviated "maximum rectified current"; the maximum repeatable peak reverse voltage (Maximum Recurrent Peak Reverse Voltage), abbreviated as "maximum reverse voltage". Another important parameter is the maximum reverse recovery time (MAX, Reverse Recovery Time),as described earlier.


Readers can imagine what to do if you were asked to name the rectifier diode.


For a specific rectifier diode, it is obviously reasonable if its model can contain its two most important parameter information. This is indeed the actual practice of many diode tube manufacturers. In practice, there are two forms of naming, including "maximum rectified current" and "maximum reverse voltage".


One is to combine the values of "maximum rectified current" and "maximum reverse voltage" into the digital part of the model, with letters before and after the number. For example, 2045 of the "STPS2045CT/CF/CG" models produced by ST are the numerical combination of "maximum rectified current" and "maximum reverse voltage". 20 represents its "maximum rectified current" of 20A and 45 represents its "maximum reverse voltage" of 45V. the prefix STP is the series name and the suffix CT/CF/CG is the classification. The author refers to this naming method as the "straight standard method".


The other is to combine the value of the "maximum rectified current" with the value of the "maximum reverse voltage" level code into the numerical part of the model, with letters before and after the number. For example, the common fast recovery diode FRIIV (FR represents the fast recovery diode, II represents the two-digit value of the "maximum rectified current", and V represents the value of the level code of the "maximum reverse voltage").


The corresponding relationship between the value of the maximum reverse voltage level code and the voltage, as shown in Table 1.


Table 1 the corresponding relationship between the value and the voltage.


For FR107, the value of 10 represents its "maximum rectified current" of 1.0A, and 7 represents the value of its "maximum reverse voltage" rating code, corresponding to 1000V. For FR203, the value of 20 represents its "maximum rectified current" of 2.0A, 3 represents the value of its "maximum reverse voltage" level code, corresponds to 200V, and so on.


Finally, a system naming method is introduced.


In switching power supplies, the naming method of "1N + four digits" (such as "1N4148", "1N5408") is often seen. This is actually a system naming method. There is no particularly obvious correspondence between the four digits in the model and the values of "maximum rectifier current" and "maximum reverse voltage". For this naming, its parameter information should be clarified by looking at its data table.


If you want to know more, our website has product specifications for the whole bridge and rectifier diode, you can go to ALLICDATA ELECTRONICS LIMITED to get more information