IPC CID EXAM QUESTIONS AND VERIFIED
ANSWERS
Question 1
What is special about thermal vias?
Correct Answer
They must be connected to board-level planes
Question 2
What is a test coupon?
Correct Answer
Companies find them beneficial and incorporate them into board production panels
to not waste a good board in production
Question 3
What is the CTE for copper, brass and aluminum?
Correct Answer
Copper: 17-18 ppm/C; brass: 19 ppm/C; aluminum: 24 ppm/C
Question 4
What is a supported hole?
Correct Answer
A hole that has the inside surfaces plated or otherwise reinforced
Question 5
What is a socket?
Correct Answer
A receptacle used if a part frequently needs replacing
Page 1 of 51
,Question 6
What is the purpose of ICT, AOI, AXI?
Correct Answer
To reduce board defect rates
Question 7
What is a subassembly enclosed by?
Correct Answer
A phantom line
Question 8
What do producibility levels tell us?
Correct Answer
Increasing complexity of tooling, materials, and processing. Yields increase as costs
decrease, etc.
Question 9
When performing testing in a clamshell fixture, what is the minimum square land
required?
Correct Answer
36 mils (0.9mm)
Question 10
What is the preferred method of hole dimensioning in relation to other holes?
Correct Answer
The second picture in the book in figure 9.2.8
Page 2 of 51
,Question 11
When can you swap pins?
Correct Answer
When your gates are within the same logic family
Question 12
Where can you guarantee no misses?
Correct Answer
See IPC 7351-5.7 chart, answer is 1mm
Question 13
What is it called when a land is only present to balance the construction of the board?
Correct Answer
Nonfunctional lands
Question 14
What does the assembly drawing documentation include?
Correct Answer
Hardware torqueing requirements
Question 15
What does a grid system being basic mean?
Correct Answer
The intersection of the lines has no tolerance
Question 16
How are grids designed?
Correct Answer
They are located with respect to a minimum of two datums
Page 3 of 51
, Question 17
What are tooling holes?
Correct Answer
Very tightly toleranced unsupported holes
Question 18
What is a buried via?
Correct Answer
A via that extends only between conductive layers with no exposure to the outside
world
Question 19
What is the common panel size in the US?
Correct Answer
18" by 24"
Question 20
What are bus bars?
Correct Answer
They are preformed components and serve the function of providing most of the
power and ground distribution
Question 21
What is the first consideration when deciding if a part can be transitioned from SMT
to TH?
Correct Answer
It must be determined if the leads can be bent or not
Page 4 of 51
ANSWERS
Question 1
What is special about thermal vias?
Correct Answer
They must be connected to board-level planes
Question 2
What is a test coupon?
Correct Answer
Companies find them beneficial and incorporate them into board production panels
to not waste a good board in production
Question 3
What is the CTE for copper, brass and aluminum?
Correct Answer
Copper: 17-18 ppm/C; brass: 19 ppm/C; aluminum: 24 ppm/C
Question 4
What is a supported hole?
Correct Answer
A hole that has the inside surfaces plated or otherwise reinforced
Question 5
What is a socket?
Correct Answer
A receptacle used if a part frequently needs replacing
Page 1 of 51
,Question 6
What is the purpose of ICT, AOI, AXI?
Correct Answer
To reduce board defect rates
Question 7
What is a subassembly enclosed by?
Correct Answer
A phantom line
Question 8
What do producibility levels tell us?
Correct Answer
Increasing complexity of tooling, materials, and processing. Yields increase as costs
decrease, etc.
Question 9
When performing testing in a clamshell fixture, what is the minimum square land
required?
Correct Answer
36 mils (0.9mm)
Question 10
What is the preferred method of hole dimensioning in relation to other holes?
Correct Answer
The second picture in the book in figure 9.2.8
Page 2 of 51
,Question 11
When can you swap pins?
Correct Answer
When your gates are within the same logic family
Question 12
Where can you guarantee no misses?
Correct Answer
See IPC 7351-5.7 chart, answer is 1mm
Question 13
What is it called when a land is only present to balance the construction of the board?
Correct Answer
Nonfunctional lands
Question 14
What does the assembly drawing documentation include?
Correct Answer
Hardware torqueing requirements
Question 15
What does a grid system being basic mean?
Correct Answer
The intersection of the lines has no tolerance
Question 16
How are grids designed?
Correct Answer
They are located with respect to a minimum of two datums
Page 3 of 51
, Question 17
What are tooling holes?
Correct Answer
Very tightly toleranced unsupported holes
Question 18
What is a buried via?
Correct Answer
A via that extends only between conductive layers with no exposure to the outside
world
Question 19
What is the common panel size in the US?
Correct Answer
18" by 24"
Question 20
What are bus bars?
Correct Answer
They are preformed components and serve the function of providing most of the
power and ground distribution
Question 21
What is the first consideration when deciding if a part can be transitioned from SMT
to TH?
Correct Answer
It must be determined if the leads can be bent or not
Page 4 of 51
