Electrical Level 3 BCIT – Electronics Questions With Complete Solutions

Electrical Level 3 BCIT – Electronics Questions With
Complete Solutions


DIAC leads
MT1 and MT2
What is a LASCR
A SCR that is activated by the application of LIGHT
What does "bilateral" refer too in a a DIAC
that it can conduct in both directions
A UJT is considered a __________ device
SWITCHING
for a UJT what is the "Intrinsic Standoff Ratio"
RB1 / (RB1+RB2)

determines the trigger voltage
is a UJT current OR voltage sensitive
Voltage
What conditions are needed for a UJT to conduct
The Emitter voltage needs to be 10v higher than Base 1

Ve > n*Vbb+0.7v
How to turn of a UJT

, The emitter cant be more than 3v higher than Base 1
The resistance between Base 1 and Base 2 when the UJT is off
is approx
4 - 10 K-ohms
making the base of a PNP transistor less negative will
turn it on less
N- type Semi conductors have an excess of
Electrons
P - Type Semiconductors have an excess of
Holes
SCR's are different from TRIAC's because
The SCR has an Anode and Cathode.

Triac has MT1, MT2, Gate
A triac will turn on when
T1 is positive compared to the T2. The gate is negative
compared to T1
A DIAC will conduct when there is enough ____ applied to it
Voltage
An SCR is only triggered when
The Anode is Positive and the Cathode is Negative
When a BJT is saturated, the