Introduction: The basic characteristics of microwave oven high voltage rectifier diode CL01-12 are measured here. By measuring its forward conduction voltage, it can be seen that it needs more than 9V to be turned on. By smashing its epoxy encapsulation, its internal structure can be seen, which is a high-voltage diode formed by a stack of 13 layers of silicon diodes.
关键词: Microwave , Finishing , Diode
§ 01 Microwave Diode
1. Background introduction
A few days ago, I saw a video of watermelon introducing, how to identify the quality of microwave diodes. Direct measurement of diodes with a multimeter cannot measure the forward conduction of the diodes, and a test pen is required to test. These are two microwave oven diodes purchased from Taobao. Let's check their basic electrical characteristics.
2. Basic measurement
First measure the size of the high voltage diode, its diameter is 7.33mm, and its length is 21.92mm. This is the CL01-12 data sheet, where the nominal dimensions, which give the length of the diode, and the corresponding diameter parameters, are the same as the measured results.
3. Electrical Characteristics
In the following, we measure the voltage across the diode and the voltage on the sampling resistor respectively by means of a digitally adjustable voltage, so as to obtain the VA characteristic of the diode. This is the measured CL01-12 high voltage diode forward VA characteristic curve. It can be seen that its conduction voltage is above eight volts, which makes it very difficult to measure its forward conduction characteristics with an ordinary multimeter.
According to the parameters of the data sheet of the diode CL01-12, its reverse internal voltage is as high as 12kV, and it is impossible to measure such a high reverse breakdown voltage according to my current equipment.
4. Internal structure
Why is CL01-12 able to withstand high voltage, and why is its forward voltage so high? Is this related to its special structure? Use a hammer to break the epoxy encapsulation on the outside of the diode. This is the broken diode.
Below they are placed under a magnifying glass for observation. It can be seen that it has a multi-layer stack structure inside. There are about 13 layers in total; if each layer is a diode, then the total diode internal voltage is the sum of the withstand voltages of all diodes.
Next, use a multimeter to measure the on-voltage between the stack structures inside the CL01-12. If the direction is wrong, the multimeter will not conduct. After changing the direction, the forward conduction voltage can be measured. The lowest turn-on voltage is around 0.7V. This shows that CL01-12 is a stack of multilayer silicon diodes.
※ Summary ※
The basic characteristics of microwave oven high voltage rectifier diode CL01-12 are measured here. By measuring its forward conduction voltage, it can be seen that it needs more than 9V to be turned on. By smashing its epoxy encapsulation, you can see its internal structure, which is a high-voltage diode formed by stacking 13 layers of silicon diodes.
