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PCB Questions
Question 1 of 40
On a PCB, the low power part and the high power part have to be spread
sufficiently to avoid ______.
a. capacitive and inductive coupling between power circuits
b. crosstalk
c. only inductive coupling
d. only capacitive coupling
Question 2 of 40
Which of the following is a base material used in the manufacturing of flexible PCBs?
a. Epoxy resin
b. Polyester foil
c. Teflon foil
d. All of the above
Question 3 of 40
Which of the following is a characteristic parameter of a photographic material?
a. Density
b. Resolving power
c. Exposure latitude
d. All of the above
Question 4 of 40
The microstrip line is derived from a ______.
a. conductor on the ground
b. conductor below the ground
c. conductor above the ground
d. None of the above
Question 5 of 40
Which one of the following is not a plating technique?
a. Immersion plating
b. Electroless plating
c. Hard plating
d. Electroplating
Question 6 of 40
Screen printing is used in ______.
a. photo printing
b. screen printing
c. hand pri nti ng
d. All of the above
Question 7 of 40
If Ohmic losses are neglected, the wave impedance ZW in a homogenous material can
be calculated by using the formula.
a. Zw=(L/C)1/2
b. Zw=(2L/C)1/2
c. Zw=(2C/L)1/2
d. Zw=(C/L)1/2
Questian 8 of 40
Which of the following techniques is used in mass soldering?
a. dip soldering
b. drag soldering
c. wave soldering
d. All of the above
Question 9 of 40
Which of the following is a design constraint forthe design of the flexible PCBs?
a. Current carrying capacity of the conductors
b. Bending
c. Contours
d. All of the above
Question 10 of 40
The skin-effect losses are sometimes also called
a. semiconductor losses
b. coductor losses
c. insulator losses
d. None of the above
Question 11 of 40
How much copper surface is reserved on multilayer boards for the solderability
test?
a. 20x70mm
b. 10x50mm
c. 20x70cm
d. 10x50cm
Questian 12 of 40
The inks used in screen printing are mostly
a. acid based
b. alkali based
c. vinyl based
d. All of the above
Question 13 of 40
Which of the following tests is done for quality control for multilayer boards?
a. Electrical and metallographic test
b. Continuity between lagers test
c. Insulation resistance between lagers test
d. All of the above
Question 14 of 40
The fundamental principle of electrolysis is understood from
a. Ampere's law
b. Faraday's law
c. Ohm's law
d. Coulomb's law
Question 15 of 40
Which of the following is a disadvantage of a solder mask?
a. Less contamination of the solder alloy
b. Avoidance of solder bridging
c. Its capability with the flux has to be verified before use
d. Improved flexural strength
Question 16 of 40
What is hot air leveling used for?
a. Etching
b. PCB finishing
c. PCB layout
d. PCB artwork
Question 17 of 40
Which of the following is a technique for the generation of the circuit pattern on
metal core boards?
a. Substance additive processing
b. Additive processing with catalytic adhesive
c. Semi-additive processing
d. Both a and b
Question 18 of 40
Polymeric materials exhibit a very high resistance to
a. temperature variations
b. pressure
c. humidity
d. elasticity
question 19 of 40
Removing the resists from the board in photo printing is called
a. Post backing
b. stripping
c. touch up
d. dyeing
Question 20 of 40
Which of the following is a coating process for wet film resists?
a. Flow coating
b. Roller coating
c. Dip coating
d. All of the above
Question 21 of 40
All the processing steps for manufacturing ultra thin foils except ______
are conventional
a. drillig
b. alumiium foil removal
c. fortification
d. etching
Question 22 of 40
Mlultiwire boards are used in
a. the implementation of high density electronic circuits
b. the implementation of low density electronic circuits
c. the implementation of power electronic circuits
d. the implementation of power suppler circuits
Question 23 of 40
Which of the following is not a film used in PCB design?
a. A copper film
b. A polyester film
c. A photographic glass
d. A tri-acetate film
Question 24 of 40
A standard hole(0.8mm) in a PCB design is represented by which symbol
a. Ο
b. €
C. Ө
d. β
Question 25 of 40
Etch back is a technique by which ______
a. epoxy smear is removed and the exposed glass fibers prepared for copper deposition
b. epoxy smear is deposited and the exposed glass fibers prepared for copper removal
c. etchants are removed again
d. None of the above
Question 26 of 40
What would be the simplest and most suitable remedy for electro-magnetic coupling between two wires?
a. To increase the space between two wires
b. To increase the lamination between two wires
c. To twist the both wires
d. To decrease the spacing between wires
Question 27 of 40
Which of the following is a type of soldering fluxes?
a. Corrosive flues
b. Intermediate fluxes
c. Non-corrosive fluxes
d. All of the above
Question 28 of 40
In which of the following ways can the required quantity of heat for the melting of the solder be supplied?
a. Iron soldering
b. Hot gas soldering
c. Radiant heat soldering
d. All of the above
Question 29 of 40
Parasitic effects influence the working of a PCB
a. true
b. false
c. sometimes true and sometimes false
Question 30 of 40
A conductor in a printed circuit should be considered a transmission line if its length I(in meters) is
a. I>Tr/100 nsec(Tr- rise time of pulse)
b. I>2Tr/100 nsec
c. I>Tr/200 nsec
d. I>2Tr/50 nsec
Question 31 of 40
Which of the following is not a machine cleaning process for boards?
a. Sanding
b. Water rinse
c. Wet brushing
d. Scrubbing
Question 32 of 40
Under which of the following conditions is a multilayers board used?
a. Where the overall PCB dimensions and interconnections are not feasible on a double-sided
b. Where reduction in electronic equipment weight and volume is the prime concern
c. Where decoupling and shielding of the interconnections is important
d. All of the above
Question 33 of 40
The biggest problem associated with striplines and microstrip lines is the
a. low attenuation per unit length
b. high attenuation per unit length
c. low impedance per unit length
d. high impedance per unit length
Question 34 of 40
Cupper plating is done in multilayer boards to_____
a. remove etchants
b. remove excess copper
c. withstand thermal shock due to soldering
d. clean a PCB writh chemicals
Question 35 of 40
The biggest disadvantage of flexible PCBs is that
a. they can not be used for low frequency applications
b. they are not suitable for high frequency applications
c. they can be used only in military applications
d. they can used only in aerospace applications
Question 36 of 40
Crosstalk is much less dangerous in which of the follovring
a. ECL-ICs
b. TTL-ICs
c. RTL-ICs
d. CMOS-Cs
Question 37 of 40
Which of the following is not a basic ingredient of a copper clad laminate?
a. Filler
b. Resin
c. Silver foil
d. Copper foil
Question 38 of 40
To reduce the skin-effect losses, what is required to be done
a. decrease PCB thickness
b. increase PCB thickness
c. keep line length large
d. Non e of the above
Question 39 of 40
Under etching can be minimized bar keeping the etching time
a. as short as possible
b. as long as possible
c. equal to 5 minutes
d. equal to 30 seconds
Question 40 of 40
Current spikes in TTL circuit boards can be eliminated by which technique
a. removing the TTL circuit
b. replacing transistors with diodes
c. using a ground line
d. All of the above
Please email to aldpcb@aldpcb.com for anwsers, thanks.
Please email to aldpcb@aldpcb.com for anwsers, thanks.
