Service manual
--
PC
-
1GOO
4.
CMT
interface
The
CMT
int erface consists of the
followin
g circuits:
• Write circuit
• Read
circuit
• Remote circuit
4-1
. Write circuit
As shown below, the logic level signals are converted
into
si
gnals
of
mi
cro level.
•
Hi
gh frequency
component
of
signal
is
el
iminated.
-+
I L
ow
pass
filter
I
• As a
3KHz
component drops 6dB than a
105
KHz com·
pone
nt
because of
the
low pa
ss
filt.ef, compensation
is
therefore done
....
IH
igh
frequency
co
mpensation I
• The ou
tput
level
is
set to
th
e micro level. -+IAtte
nuat
ion I
•
DC
co
mp
o
nent
is cut.
"'1
DC decoupling I
CM
T
OUT_
4.7VPP - vee
•
Low
pan
filter
• High
frequency
compltn"tjon
~
MIC
•
Al1enu.'ion
r:--.nnfi
• DC dec:oYpling N\I\-=:I
~.5mV
PP
lmVAMS
RI
C2
RZ
C
MTOUTOO--~·~
'~'
C-~
lr--1IC_--~--'_----.n
1
2KO
O.047pF 6.81(0
MIC
Cl
T R3
680n
'--v--'
•
Low
PI"
H
ig
h
Attenunion
filt... frequency
~olnlM""'
l
io
n
Cl , C2 : DC decuppling
Output
l
evel
:
3mV
rms
Output
impeadance: APR
OX
600n
4-2. Read circuit
1Mn
CM
T
IN
...
-~~-(-----t'l
-
-4-
-
-}-
....
'~1
.........
O
_.{'
"~F
....
_V"
:looKO
EAR
1
CONTRO'
t
L..
__
__________
...1
1K
n
Inside gate .r!'lV
T
he
read signal amp
li
fier circuit consists
of
the
same
type
as
that of the CE·
l50
. The circuitry is contained inside the
gate array in the case
of
the CE-l600P.
4-3. Remote circuit
For th e relay (AG8229 or G5AK·287
P)
is
a two-coil
latching
type,
A ON (or
OFF)
pulse must
be
gi
ven
to
tho
acti
va
te (or deactive) the relay through
the
driver of the
gate array,
in
order to turn the relay active.
{See
Fig.S.)
The width of pulse must be more than 5 milliseconds than
that mentioned
in
the relay specification.
Wit
h the
CEo
1600P, it
is
set to about 10 milliseconds.
The following sign
al
formats are used for the casse
tt
e
interfacing signals.
Write
Read
P
WM
method (1
600
method)
PW
M
method
(1600
method) and
,
500
method
5. Power supply circuit
5-1. Power supply
VP, VBAT,
and
battery recharge circuits
AM
-
l0Z
(x2)
AC
Adaptor 01
02 03
About
8.4V.
__
...
-.
__
~
........
c_,_--
--------
-
68
-
- VP (6.4V)
RK
-13
Ac
50
04
05
~...,.-ll!---
.....
--~--T·
V BAT
Nicd ..:..
AAx5
:
1
AK
-
13
06
'10Q03
j
lA
) x 2
01
: F
Q(
prevent
io
n
of
reverse current to the rechar-
geable battery
to
the adaptor.
To achieve efficient recharging of the battery, a
Schottky barrier
type
diode
RK
-13 (1
.7
Al
is
used
.
02.
03
: These diodes are used to drop
the
voltage from the
printer to less
th
an
printer driving voltage
(7
.15V
max.).
04
:
05
:
06
:
For pre
ve
ntion of reverse
cu
rrent
fr
om
VP
to the
rechargeable battery. when
the
adaptor
is
being
used.
For prevention
of
reverse current from V
BAl
(PC-l600) to VP (printer).
The diode
is
a
Schottky
battery type for avoiding
battery exhaustion when the adaptor
is
used.
To avoid exhaustion of the battery
in
the
main
unit when
the
rechargeable battery
is
used, OS
is
used to bypass
04
and
05
.
To
meet the
pr
inter drive
vo
ltage (5.0V, min
.1.
tile
rechargeable
battery
low voltage
is
set to
5.S5V
limit (1.13V per battery).
After the main unit battery
is
ORad with
the
VBAT supplv
from
the
CE
.
l600P
, vec
is
regulated to 4.7V before
supplied to tile
CE
-
l600P.
(See
the
figure below.)
When
the
main unit
powe
r is turned off. vce
is
not sup.
plied.
CE
1600P
PC
1
600
(Main
unit)
vee
'0_
'
rL
J
VB
AT
. ! , 1 reg
ulato
r
-:-UM-3
~
(x
4)