3 PCBs

Question 1

What are air gaps designed to do?

Answer 1

Create a non-conductive sections between two points
Reduces chance of voltage flowing unintentionally through the device

Question 2

What is clearance?

Answer 2

The distance between conductive components
Important when routing and placing components

Question 3

What are the 3 classes of PCBs?

Answer 3

Class 1: General electronics e.g. TV remotes, children’s toys
Class 2: Long lifespan electronic devices e.g. Smart phones, laptops
Class 3: Hish reliability devices that should not experience downtime e.g. life support machines

Question 4

Name the 11 PCB layers in order

Answer 4

Top layer
Prepreg
Internal ground plane
Core
Internal routing layer
Prepreg
Internal routing layer
Core
Internal power plane
prepreg
Bottom layer

Question 5

What angle should layers be to eachother and why?

Answer 5

90 degrees
Reduces interference and helps with signal routing

Question 6

What things you must consider with PCB traces?

Answer 6

Width and spacing
Size and pitch of component pads
Length of trace
Shape

Question 7

What are rules for placing components?

Answer 7

Keep power components together to reduce noise on other components
Keep related components together
Isolate noise sensitive components
Use stitching to ensure a good connection between layers
Use ground and power planes when possible