How many types of cmponents in PCB Assembly?

As for PCB Assembly,  Components are mainly divided into two types: DIP and SMD.

                   The SMD (surface mount device) surface mount components.

What's the meaning of 0603, 0805 and 1206 in SMD?

In fact, it refers to the package size of the component, and the size of the element is the length and width of the (width). The unit used can be inch or mm. The resistance and capacitance of SMD are usually described by inch. A total of 4 digits represent a group of 2 single digits.

0603:  0.06"x0.03"，or 60x30 mils，or 1.6x0.8mm   (Note: 1mil=1mil-inch)

0805:  0.08"x0.05"，or 80x50 mils，or 2.0x1.25mm

1206:  0.12"x0.06"，or 120x60 mils，or 3.2x1.6mm

Sometimes components may also use metric mm to indicate their size. Dimension 1608 (mm) corresponds to 0603 (inch).

The correspondence is as follows:

What's the SMD Resistance Specification?

The dimensions know, of course, its specification. SMD resistance values are directly marked on the components.

The SMD resistance representation is as follows:

What's the SMD capacitance Specification?

There are many different types of capacitors, mainly made of different materials, such as ceramic capacitors, tankage capacitors, electrolytic capacitors, etc. Only a large capacitor has a positive and negative electrode (cognition capacitor)

In the case of SMD capacitors, they are not marked like resistors, so what? It can only be seen from the specifications on the tape, but in principle, the larger the volume of the SMD capacitor element, the larger the capacitance value.

The specifications on tape show 104,103 similar values, with capacitance values of. 104. As shown in the graph above, the 4th power PF of 10x 10 = > 100000 pf = 100nF = 0.1uf. Similarly, 330 represents 33pf.

At the bottom of the SMD led component is a bright blue light on the left and a green light on the right. Because led has polarity, green dots are marked to indicate that this edge is the cathode of led.

How about the specification of other SMD Components?

Transistor (transistor) (small outline transistor), such as SOT-23 for SMD

IC (small outline IC ), for SMD such as SOIC-8 / SOIC-16

The more pin the IC has, of course, the more different encapsulation technologies (that is, the case wrapper for die) will emerge, for example,

TQFP (Thin Quad Flat Pack)，100 or 144 pins

PQFP (Plastic Quad Flat Pack)，208 or 240 pins

BGA (Ball-Grid Array)，256 to 1000+ pins