PCB Assembly Methods Flashcards
Which is the oldest method of PCB packing?
Pin through hole
What are the pro’s of a pin through hole packaged PCB?
Pro’s:
-Stronger than surface mount technology.
-Visual inspection of solder joints is satisfactory to determine the quality of the joint.
What are the con’s of a pin through hole packaged PCB?
They use up a lot more space than SMT pcb’s
Describe the pin through hole PCB packing method.
A hole is drilled through the PCB.
Component pin is pushed through the hole.
The pin is soldered to the underside of PCB. (Other side to the component).
What was one of the first uses of pin through hole packaging?
I’m artillery shells in ww2
Describe Surface Mount Technology.
The component has a high density of pins and is soldered or glued to the surface of the component.
Describe the advantages of SMT.
-Higher density connection
-Takes up less space on the PCB.
Describe the disadvantages of SMT
It is a weaker connection than PTH.
What does the term ‘Pitch’
The amount of electronics you can fit into a given area of a PCB
What was the first type of circuit component?
Dual in line Pin through hole Circuit.
Describe DIL pin through hole circuits
- Low density
- first package type
- the chip is wire bonded to a lead frame
-Imperial measurements
What are the limits of DIL circuits?
- 40 legs
- smallest pitch of 0.1” before legs become too weak.
Which type of circuit succeeded DIL circuits?
SMT integrated circuits
What was the pitch of the first SMT integrated circuit?
0.05”
Describe area array packages.
- Ball Grid Array connection on underside of component.
- 1.5mm pitch
