Verified Answers |Already Graded A+
What are key cost drivers for bare board manufacturing? - ANSWER-
Laminate materials/mixed dielectrics, number of layers, total number of
holes, minimum hole size, panel utilization, lamination cycles, co-
planar, plated via-in-pad epoxy filled, back-drilling, impedance control
DRC's for fabricators and assemblers often do not take into account
what type of DRCs - ANSWER-electrical DRC's such as controlled
signal lengths for timing
Rectangular sheet of base material that is used for the processing of 1+
printed boards, and when required, one or more test coupons -
ANSWER-Fabrication Panel
Printed board image/patterns plus the additional contiguous deliverable
material from the panel (+ tabs, fiducials, tooling holes, etc...) -
ANSWER-Assembly Array
What is the most common size panel? - ANSWER-18x24in,
460x610mm
Page 1 of 25
,Stencil manufacturer work to what location/ - ANSWER-Nominal
positioning location between two-dimensional variations
What should the designer consider adding to help the stencil
manufacturers? - ANSWER-Alignment fiducials
What ratio should you never go beyond in terms of the length-to-width
ratio? - ANSWER-12:!
How do long, thin boards jeopardize conductor routability? - ANSWER-
Routing is primarily on the longitudinal axis and may cause crosstalk
and signal integrity problems
What is the benefit of copper balancing? - ANSWER-Uniform exposure
to the etching solutions
Addition areas of copper foil intended to draw copper in the plating bath
away from the fine conductor images; uniform plating distribution -
ANSWER-Plating Thief
What important effect is reduced as an output from copper balancing
from the center to either side in the laminated product - ANSWER-Bow
and Twist
Page 2 of 25
, What can help straighten a board that does not have proper copper
balance from bow and twist? - ANSWER-Mechanical features like heat
sinks and stiffeners
What thermal management technique transfers the heat down to a cooler
plan/surface? - ANSWER-Thermal vias
Thermal energy/heat that is transferred by electro-magnetic radiation
primarily in the infrared (IR) wave length - ANSWER-Radiation
How do large cores/large copper affect the reflow profile? - ANSWER-
Significant heatsink and impact the reflow of the solder surfaces
What is highly advisable to do when a board contains a metal core? -
ANSWER-Add a note on the Assembly Drawing
Why does 0402 equate to 0.03936~" x 0.01968~" not 0.04"x0.02"? -
ANSWER-Inaccurate round offs
What are the 3 vantage points of dimensioning? - ANSWER-Mechanical
Constraints Drawing (mating the PCB with the mechanical housing),
PCB Master Drawing, QA inspection criteria (ensure conformance of
manufactured product for intended usage)
Page 3 of 25