An LED chip is actually a light emitting diode that emits light when loaded with a certain voltage and current. Generally speaking, the voltage of a single led chip is about 3V and the current is 30mA. The LED chip
voltage and current of LED chips are mostly determined by the series-parallel connection of LED chips in the LED package process
The 0.2W LED chip most used in the lamp tube is formed by connecting two LED chips in parallel, namely 3V and 60MA. The high-voltage LED 9V chip, which is used most for RC power supply, is formed by connecting three LED chips in series, namely 9V and 30MA.
Because LED chips are made up of multiple LED chips connected in series and in parallel, there can be many specifications and voltages for LED chips. The exact voltage of the chip can also be determined by how many LED chips the chip is made of. Of course, because LED chips and the bonding gold wires are relatively small, visual inspection can only make a rough estimate. The exact amount is measured by using a DC source.
However, 3V,6V,9V and so on are used more frequently. Of course, there are also chips with several tens of V. The kind of chips depends on the specific design scheme.
For a chip with only 3V, the diode bar of a multimeter can be used to light the chip. This one has positive and negative values. If it is not bright, just change the positive and negative values. For LED chips with unsure voltage, it can only be measured by DC source. The method is to set the voltage of DC source to zero, the current to the maximum, connect the positive and negative electrodes of the chip, and adjust the voltage of the current source to increase from zero. When the chip is slightly bright, the voltage at this time is the approximate voltage of the LED chip.
It is the same principle for COB chips
, but the voltage and current will be relatively larger because COB package
s more LED chips. The voltage and current of COB chips are also measured by DC source.
Using DC source is the simplest and direct method, which is used most in the development process.
Each type of chip has its own characteristics, some with higher cost performance and some with better performance. However, LED chips of the same specification will vary from manufacturer to manufacturer. Therefore, LED chips are not absolutely good or bad. As long as they are used well, they will play their greatest role.