Object-To
plot
the drain
and
transfer characteristics
of
Field
Effect
Transistor
(FET
No.
BFW
10).
Apparatus
required-
1)
FET-BFW
10.
2)
Two
voltmeters,
one
milli
ammeter.
3)
Variable
power
supply
-one
0-3
volts
for
VGs
and
one
power
supply
0-15V/18Volts for VDs
4)
Connecting
wires
(patch
cords
with
banana
plugs)
Manipulations-
PART-1
Drain
characteristics
(variation
of
Ip
with
Vos)
1)
Make
connections
as
shown
in
the
circuit
diagram
(fig
1).
2)
Keep
the
gate
source
voltage
at
0
volts.
Now
change
the
drain
source
voltage
(Vos)
from
0
volt
upwards
in
steps
of
convenient
value
(say I volt)
up
to
16
volts.
Note
down
the
value
of
drain
current
corresponding
to
each
value
of
Vps
3)
Repeat
the
above procedure
for
different
values
of
gate
source
voltage
Vos
4)
For
drain
characteristics
draw
graphs
between
I p
and
Vps
for
each
value
of
Vos
(as shown in fig.3)
5)
From
the
graph find
out
the
value
of
VDs
at
which
the
drain
current
becomes
constant.
This
is
called
the
Pinch
Off
voltage.
PART-2
Transfer_
characteristies
(variations
of
Ip
with
VGs)
1-For
Transfer
characteristics,
keep
the
source
drain
voltage
Vps
at
a
value
greater
than
the
pinch
of
f
voltage
as
a
recorded
above(say
Vps'
= 5 volt).Now
change
the
gate
source
voltage
Vos
in
steps
of
convenient
value.
Note
down
the
value
of
drain
current
corresponding
to
each
value
of
Vos.
Continue
this
process
till
the
drain
current
becomes
zero.For
transfer
characteristics
curve,
drawn
graph
between
p
and
Vas.
(as
shown
in
fig.4)
