Packaging Technology on PCB Circuit Boards

The COB package on the PCB circuit board, if the bare chip is directly exposed to the air, it is easy to be polluted or artificially damaged, which affects or destroys the function of the chip, so the chip and the bonding wire are encapsulated with glue. People also call this type of encapsulation a soft encapsulation. The full name of COB package is Chips on Board (COB), which is a technology to solve the problem of LED heat dissipation. It is to adhere the bare chip to the interconnect substrate with conductive or non-conductive glue, and then perform wire bonding. Its electrical connection.

1. What is COB soft package

Careful netizens may find that there is a black thing on some circuit boards, so what is this thing? Why is it on the circuit board and what does it do? In fact, this is a kind of package. We often call it a soft package. It is said that the soft package is actually hard. Its constituent material is epoxy resin. We usually see that the receiving surface of the receiving head is also this material. Inside is a chip IC. This process is called bonding, and we usually call it bonding. This is a wire bonding process in the chip production process, namely chip-on-board packaging, which is one of the bare chip mounting technologies, using epoxy resin to mount the chip on the PCB circuit board.

2. Features of COB soft package

This kind of soft packaging technology is often for cost. As the simplest bare chip mounting, in order to protect the internal IC from damage, this kind of packaging generally requires a one-time molding, which is generally placed on the copper foil surface of the circuit board. It is round and the color is black. This packaging technology has the advantages of low cost, space saving, light and thin, good heat dissipation effect, and simple packaging method. Many integrated circuits, especially most low-cost circuits, only need to be integrated in this method. The circuit chip is led out with more metal wires, and then handed over to the manufacturer to place the chip on the circuit board, solder it with a machine, and then apply glue to solidify and harden.

3. Application occasions

Because this kind of package has its own unique characteristics, it is also used in some electronic circuit circuits, such as MP3 players, electronic organs, digital cameras, game consoles, etc., in pursuit of low-cost circuits. In fact, COB soft packaging is not only limited to chips, it is also widely used in LEDs, such as COB light source, which is an integrated surface light source technology that is directly attached to the mirror metal substrate on the LED chip.