TPC 251 Semiconductors Flashcards
Raising temperature of a semiconductor material _________ its ________
increases; conductivity
Boron acts as an _______ when added to silicon, making a ______ type semiconductor material.
Acceptor; P
When a junction diode conducts, electrons move _______ the junction and holes move _______ the junction.
toward; toward
As the voltage across a forward based junction diode increases beyond the barrier potential, the current
increases rapidly
Light shining on the photoconductive cell increases the cell’s
current carrying ability
Among the environmental problems of semiconductors ________ is almost always caused by human contact.
ESD
Most semiconductors can be damaged by an accidentally applied potential difference as low as ______ volts.
100
You can neutralize a positively charged nonconductive material by
Exposing it to negative ions
Soldering irons used with semiconductors devices should be in the rage of ______ watts.
25 to 30
The simplest way to protect semiconductors against RFI is to
provide enough distance
Printed circuit boards provide several advantages over direct wiring, including
better relaibility
Printed circuit boards having several layers are generally ________ than single layer boards
more complex in function
Unlike conventional PCB methods, SMT allows
High-speed automated assembly
The advantage of edge connections over pin connectors for mounting PCBs include
smaller size
If you must attempt to repair a PCB that has a conformal coating you should
remove coating from the repair site only
The base in a non bipolar junction transistor is made of _______ type material lightly doped with ______ material.
P; acceptor
In order for a non transistor to function as an amplifier without distortion, it must operate in the ________ region.
active
The most common transistor connection is the common ______ because it provides ______ gain in voltage and current.
emitter; high
If a transistor operates as a switch, it is ON when it operates in the _______ region and OFF when it operates in the ______ region.
saturation; cutoff
CMOS ICs consume ________ amounts of power; making them desirable for _______ circuits.
small; complex
Compared to plastic IC packages, ceramic packages cost ______ and withstand high humidity and high temperatures _________.
more; better
The color band or dot on a DO semiconductor package indicates the
n-type region
In removing a flatpack that is glued to a PCB, you should avoid ______ because you might damage the _______
prying; PCB
A transistor has a maximum PD rating of 200 mW at 25 degrees Celsius and a derating factor of 2 mW degrees celsius. What is the maximum PD at 30 Degrees?
190 mW
The best operating point (Q point) for a transistor is near the
center of the active region
