Fig.
6-49
explains
the
details
of
the
regulated
circuit.
when
Q1
is
ON,
il
flows
through
D100
(a)
and
if
Q1
is
OFF
il2
flows
through
D100
(b)
fly
wheel
diode.
When
the
energy
is
stored
in
T100.
Total
ill
and
i12
becomes
regulated
output.
ICl00
is
pulse
width
control
IC,
R112
and
C112
which
connect
to
5
and
6
pin
makes
.
~
1
-
wnvn
nanillnfinn
r " i ’ r r ’ n i + ’
Rv
i n
h11’i‘|1’
7
niF=("P§
nf
PWN
(DHTRQ
widfh
mnd1I1¢3_f;iQn\
triangle
" ’ ~
~-~-------v
---~---f
-1
-~
~----
-
:-~e~-
--
-~~
r - - - v
---~
~v---
,
comparator
output,
controlled
pulse
output
is
used
to
drive
pulse
transformer
T3
at
8
and
ll
pin.
The
difference
Amplifier
consist
of
pin
1
and
2
control
the
output
voltage
and
Amp.
pin
15
and
16
control
output
current.
6-10-2
+l2V
Regulating
circuit
*l2V
regulator
is
obtained
as
following
method.
The
output
from
2nd
wiring
side
oscillated
by
switching
of
the
transformer
Tl
is
rectified
by
D200.
This
output
is
transformer
T1
and
switching
Tansistor
Q1.
Then,
+22V
is
gained
through
T200
to
C200.
This
+22V
is
chopped
down
to
+l2V
by
Q200,
Q201
and
IC200
is
the
same
pulse
width
control
IC
as
SV
supply
which
have
the
synchronise
operation
as
IClOO
master
and
as
IC
200
slave.
Therefore,
it
operates
under
the
triangle
wave
generating
circuit
which
was
decided
by
IC100.
p
For
that
reason,
internal
oscillator
in
IC200
has
short
circuit
of
6
and
14
pin
of
IC20O
to
prevent
operation.
IC200
outputsthe
pulse
output
to
pin
8
and
11
which
are
controlled
by
inbuilt
2
pieces
ofPWM
comparator
output,
similar
to
SV
supply.
The
direct
current
output
voltage
is
controlled
by
chopping
darlington
circuit
of
Q200
~ d
Q201,
then
output
voltage
is
obtained
through
T201,
then
output
voltage
is
obtained
nrough
T201
to
C201
which
is
insulated
to
the
lst
wiring
side.
(D201A
and
L20lB
are
the
fly
wheel
diode)
6-10-4
-l2V,
-SV
regulating
circuit
-l2V,
-SV
regulator
takes
out
the
output
which
is
oscillatedlby
switching
transformer
T1
and
switching
Transistor
Q1
at
2nd
wiring
side
of
Tl.
then,
it
is
regulated
by
D400,
D300
and
their
output
is
controlled
by
3
terminal
regulator
IC400
and
IC300,
-12V
and
-SV
output
are
obtained.
IC400
and
IC300
are
so
called
series
dropper
control
method,
unneccessary
power
becomes
loss
in
IC.
Also,
over
current
protection
and
thermal
shut
down
are
incorporated
in
IC.
The
block
diagram
of
IC400
and
IC300
are
shown
at
fig.
6-SO.
79
Содержание MB-6890
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