Download semiconductor circuit templates

Transistor Circuit Templates
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AInc.
NPN transistor circuit template
0
current
meter
+
0
p
pn junction
anode
n
volt
meter
This diode is forward biased
1 pn junction
cathode
collector
current
meter
base
0
+
emitter
n
2 pn junctions
+
0
p
current
meter
+
n
0
pn junctions
+
0
+
volt
meter
volt
meter
This transistor is in conduction
NPN transistor circuit template
When v d gets high enough, the light will turn on.
If v gets higher, the light will become brighter.
d
Voltage here, v ,
d
goes up as the
variable resistance
value goes up.
resistance
knob
is
varies
turned as
so
resistor
light
moregoes
so
knob
is
on.
light gets
turned.
brighter.
input
signal
If the input signal
and the output signal
are “grounded” at the
same potential the
circuit is know as a
common-emitter
circuit.
output
signal
+
n
+
p
n
pn junctions
+
emitter
0
volt
meter
This transistor is connected in a common-emitter circuit
+
NPN transistor circuit template
When v d gets high enough, the light will turn on.
v
1
=[ R
R
1
1
+
R
v
]vt
R
v
d
=
v
t
v
-
Voltage here, v ,
d
goes up as the
variable resistance
value goes up.
1
v
0
1
v
Variable
Resistor
+
-
n
input
signal
R
R
output
signal
p
2
n
E
Many sensors are designed
to provide a variable
resistance output signal.
This transistor is connected in a common-emitter circuit
volt
meter
t
NPN transistor circuit template
At high voltage
value, light is
ON.
high
value
v
in
Low
value
v
0
At low voltage
value, light is
OFF.
output
signal
time
R
the voltage across
these two terminals
-
n
input
signal
= v
in
+
p
1
n
E
This transistor is connected in a common-emitter circuit
Example of a digital circuit - a buffer
volt
meter
t
NPN transistor circuit template
At high voltage
value, light is
OFF.
high
value
v
in
Low
value
v
0
At low voltage
value, light is
ON.
+
time
-
n
p
R
the voltage is
applied across
these two
terminals
v
1
n
in
E
This transistor is connected in a common-emitter circuit
Example of a digital circuit - an inverter
volt
meter
t
NPN transistor circuit template
high voltage value
high
value
v
v
0
in
Low
value
+
low voltage value
time
-
n
p
R
the voltage is
applied across
these two
terminals
v
1
n
in
E
This transistor is connected in a common-emitter circuit
Example of a digital circuit - Flip-flop Output
volt
meter
t
NPN transistor circuit template
high
value
v
high voltage value
v
0
in
+
low voltage value
Low
value
time
-
n
p
R
the voltage is
applied across
these two
terminals
v
1
n
in
E
This transistor is connected in a common-emitter circuit
Example of a digital circuit - Flip-flop Output
volt
meter
t
NPN transistor circuit template
This light get brighter as
input signal is linearly
increased.
There is a voltage at the
orange node because of
the voltage divider circuit
element highlighted in
blue.
v
0
+
v
d=
v
-[
t
R
R
3
+
2
R
3
R
]vt
3
R
v
v
1
in
This input signal
is varied linearly
to brighten/dim
the lights.
d
transistor is
just barely
conducting.
R
2
volt
meter
-
n
Voltage divider
output set so
t
p
n
E
This light get
dimmer as input
signal is linearly
increased.
This transistor is connected in a common-emitter circuit
Example of a linear output circuit
NPN transistor circuit template
to the FCE
power circuit
current
meter
Reference voltage
+
V
often not used.
V
0
ref
V
current
meter
+
0
V
ref
+
n
R
sensor
n
R
p
pull up
v
R
sensor
be
p
n
E
Template for monitor circuit
Output circuit to monitor resistive sensor
R
Pull up
v
be
n
E
Template for FCE circuit
Output circuit to activate relay
NPN transistor circuit template
single
pole
to the FCE
power circuit
single
throw
V
Single pole
single throw contact set
V
+
ref
+
n
R
sensor
p
R
Pull up
v
be
n
E
Template for FCE circuit
Output circuit to activate relay
NPN transistor circuit template
motor
running
FCE
motor
FCE power
supply
Sensor is now
presenting a high
resistance to the
transistor base
circuit.
V
ref
V
+
+
U-Betch-um
R
sensor
Pressure
sensor
Our guarantee
is guaranteed
Vbe is low,
transistor is
OFF v
be
R
n
p
Pull up
n
E
pressure
circuit for PSH to activate relay
NPN transistor circuit template
motor
not running
FCE
motor
FCE power
supply
V
ref
V
+
+
R
sensor
Vbe is low,
high,
transistor is
OFF v
ON
be
R
pressure goes up
n
no current is flowing
inemitter-collector
emitter-collector
in
circuit
circuit
p
Pull up
n
E
End of Presentation
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0
current
meter