What is the black object on the PCB? Let me tell you now

PCB manufacturers, PCB designers and PCBA manufacturers explain to you what the black objects on PCB are? Let me tell you now

1. What is COB soft package

Careful netizens may find that there is a lump of black stuff on some circuit boards. What is this stuff? Why does it play a role on the circuit board? In fact, it is a kind of packaging, which we often call "soft packaging". It is said that the soft packaging is actually for "hard", and its composition material is epoxy resin. We usually see that the receiving surface of the receiver is also this material, and its inside is a chip IC. This process is called "Bonding", and we usually call it "binding".

This is a wiring process in the chip production process. Its English name is COB (Chip On Board), that is, chip on board packaging. This is one of the bare chip mounting technologies. The chip is mounted on the PCB printed circuit board using epoxy resin. Why do some circuit boards not have this packaging? What are the characteristics of this packaging?

2. COB Soft Package Features

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 one-time molding, which is generally placed on the copper foil surface of the circuit board. The shape is round and the color is black. This kind of packaging technology has the advantages of low cost, space saving, thinness, good heat dissipation, simple packaging method, etc. Many integrated circuits, Especially for most low-cost circuits, it is only necessary to lead more than one metal wire on the integrated circuit chip in this way, and then submit it to the manufacturer to put the chip on the circuit board, weld it with a machine, and then glue it to harden.

PCB printed circuit board

3. Application occasions

Because of its unique characteristics, this packaging is also used in some electronic circuit circuits, such as MP3 players, electronic organs, digital cameras, game consoles, etc.

In fact, COB soft packaging is not only limited to chips, but also widely used in LED. For example, COB light source is an integrated surface light source technology that is directly attached to the mirror metal substrate on the LED chip.

Which equipment are mainly used in PCB process production?

The production of PCB is a relatively complex process. Basically, each production link requires corresponding equipment for processing, which requires a lot of effort and cost.

1、 PCB production process (multilayer board)

2、 During PCB production, the following production equipment is required:

1. Engineering production --- photo plotter, film exposure machine

2. Opening --- opening machine, oven for baking plate

3. Laminating - browning production line, laminator, plate grinder

4. Drilling --- CNC drilling machine

5. Plate grinding machine

6. Metallized hole (PTH) -- chemical copper production line (copper sink wire)

7. Graphic transfer -- film applicator, UV exposure machine or LDI

8. Graphic electroplating -- electroplating production line

9. Dry (wet) film fading production line

10. Pattern Etching - Etching Production Line

11. Solder resistance layer production --- screen printing machine, UV exposure machine or LDI

12. Baking curing - oven, tunnel furnace

13. Surface treatment -- OSP production line or chemical nickel gold line, chemical nickel palladium gold line

14. Forming --- punching machine or CNC gongs bed, cutting machine

14. Test --- electric tester, AOI, 3DAOI.

A good PCB board has a lot to do with the PCB production equipment, especially some difficult boards, which have higher requirements on the equipment.

PCB manufacturers, PCB designers and PCBA manufacturers explain to you what the black objects on PCB are? Let me tell you now.