How do we classify common components?
During the PCBA processing, components are mainly divided into two categories: DIP and SMD.
What are SMD components?
As for SMD, we often hear 0603, 0805, 1206, so what are them?
It refers to the package of the components (size), and the dimension is length * width. The unit can be inch or mm. Generally speaking, the size of SMD resistors and capacitors tend to be described with inch. Total 4 digits but 2 digits/set.
For instance,
0603: 0.06"x0.03", or 60x30 mils, or 1.6x0.8mm (Note: 1mil = one thousandth of an 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
However, sometimes the component may also use metric mm to indicate its size.
For Instance:
Dimension 1608 (mm) corresponds to 0603 (inch)
The correspondence is as follows:
What is the specification of SMD resistor?
Since the size is known, understanding its specifications is also needed. The value of SMD resistors is directly indicated on the component itself.
This is 271 ohms
The SMD resistor representation is as follows:
Waht is the specification of capacitor?
There are many different types of capacitors, which are mainly made up of different materials, such as ceramic capacitors, tantalum capacitors, electrolytic capacitors, etc. 0, 1uF or more are considered to be large capacitance values. Large capacitors have positive and negative poles (recognition capacitors)
While SMD capacitors, unlike resistors, it can only be seen from the specifications of the Tape.
In principle, however, from the volume of the SMD capacitors, the larger the volume, the larger the capacitance value.
The specification of the Tape will show some value like 104,103, which indicates the capacitance value. For instance, 104, the same as the above representation, 10x 10 4th power pF => 100000 pF = 100nF = 0.1uF. Similarly, 330 is expressed as 33pF.
SMD capacitors are not marked with any value
330 is expressed as 33pF
Under the bottom of the SMD LED component, it is a high-brightness blue LED on the left and a green LED on the right. Due to the LED has polarity, a green dot is marked, which indicates that this side is the cathode of the LED.
SMD LED components up to 15 times the result
SMD LED component lighting effect
How about the other SMD components?
For the package of SMD Transistor, SOT (Small Outline Transistor), such as SOT-23
For the package of SMD IC, SOIC (Small Outline IC), such as SOIC-8, SOIC-16
The more pins of the IC, the more different package technologies will be derived.
For instance,
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.
