November 7, 2017|
Do you know everything about HDI PCBs? Take our quiz to find out!
Tags: Blind Via, Buried Via, dielectric, pcb assembly, pcb design, PCB Manufacturing, PCB manufacturing HDI, stackup
#1 What does HDI stand for?
High Density Impedance
High Density Interconnect
High Density Interference
#2 What is one of the specificities of HDI PCBs?
HDI PCBs have a higher wiring density per unit area.
HDI PCBs can only have microvias.
HDI PCBs never cause warpage.
#3 In a HDI PCB, microvias connect the layer with:
#4 What is not true about the dielectric constant?
As frequency increases, the dielectric constant usually decreases.
The dielectric constant symbol is Dk.
The dielectric constant of a material is not important for signal integrity.
#5 What does Tg stand for?
Glass transition temperature
Dielectric loss tangent
#6 What does the dielectric loss tangent measure?
The temperature range in which a PCB substrate transitions.
The power lost due to the material.
The insulation resistance of a PCB material.
#7 What doesn’t the via-in-pad process do?
It allows for the via to be placed within the surface of the flat lands.
It reduces the drill cycle.
It fills the via with either conductive or non-conductive epoxy.
#8 Why is the aspect ratio important?
To make sure vias can be plated properly.
To have a better control over the dielectric loss tangent.
To determine the glass transition temperature.
#9 What do you call the layer of coating between the components and the bare HDI PCBs?
The surface finish
The copper layer
The solder mask
#10 What method is used to drill holes on HDI PCBs?
#11 Why do manufacturers use sequential lamination?
To drill the buried vias and the blind vias all at once and go through the lamination process only once.
To allow prepreg to melt out the sides in order to get the PCB to a predetermined thickness.
To limit the material, traces, and pads from shifting too much and causing annular breakouts when drilling vias.
#12 What is not true about controlled impedance?
You can control impedance through the space between the signal trace and the signal return path.
You can control impedance through the annular ring that surrounds a via.
You can control impedance through the relative dielectric coefficient of a material.
#13 Which one is a step of the 0-N-0 with laser microvias HDI stackup?
The core is mechanically drilled.
The sequential lamination adds additional layers.
The mechanical drill becomes a buried via.