21
TK-190
2. D/A Converter : M62354GP (TX-RX Unit IC1)
2-1. Terminal connection
2-2. Block diagram
1
2
3
4
5
6
7
8
Do
LD
CLK
DI
Ao
1
Ao
2
NC
GND
16
15
14
13
12
11
10
9
V
CC
V
DD
Ao
6
Ao
5
Ao
4
Ao
3
NC
A
SS
M62354GP
8 bit
R-2R+Segment
D-A converter
8 bit
R-2R+Segment
D-A Converter
+ –
+ –
+ –
8 bit
Latch
8 bit
Latch
+ –
+ –
+ –
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
Address
Decoder
.......
.....
12 bit Shift Register
Ch1
Ch2
L
L
L
L
D-A
Buffer
OP amp
1
2
4
5
6
8
3
9
11
12
13
14
15
16
D-A
D-A
D-A
Ch6
Ch5
Ch4
Ch3
(6)
(6)
V
CC
V
DD
Ao
6
Ao
5
Ao
4
Ao
3
V
SS
GND
Ao
2
Ao
1
DI
CLK
LD
Do
SEMICONDUCTOR DATA
2-3. Terminal function
Pin No.
Symbol
I/O
Function
1
Do
O
12-bit shift register MSB bit data is
output.
2
LD
I
When the LD is at the high level,
the 12-bit shift register value is
loaded to the D/A output register.
3
CLK
I
Shift clock input. With the rise of
the shift clock, the input signal from
the DI is input to the 12-bit shift
register.
4
DI
I
Serial data input. Input serial data
12 bits long.
5,6
AO1, AO2
O
8-bit resolution D/A.
7
NC
–
Not connected.
8
GND
–
GND.
9
Vss
–
Terminal for determining the D/A
conversion reference low side point
level.
10
NC
–
Not connected.
11~14
AO3~AO6
O
8-bit resolution D/A.
15
VDD
–
Terminal for determining the D/A
conversion reference up side point
level.
16
Vcc
–
Power supply.
3. LCD Driver : LC75824W (Control unit IC101)
3-1. Block diagram
Common
driver
Segment Driver & Latch
Shift Register
Clock
Generator
Address
Detector
DI
CL
CE
VDD1
VDD2
INH
OSC
VDD
VSS
COM4
COM3
COM2
COM1
S51
S50
S13
S12/P12
S2/P2
S1/P1
...................
........
3-2. Terminal function
Pin No.
Name
I/O Active
Function
1~12
S1/P1~S12/P12
O
–
Segment output for displaying
13~51
S13~S51
data transferred from serial data.
52~55
COM1~COM4
O
–
Common driver output.
Frame frequency fo=(fosc/512)Hz
56
VDD
–
–
57
VDD1
I
–
Apply 2/3 the LCD drive bias
voltage from outside. If 1/2 the
bias is applied, connect to VDD2.
58
VDD2
I
–
Apply 1/3 the LCD drive bias
voltage from outside. If 1/2 the
bias is applied, connect to VDD1.
59
VSS
–
–
60
OSC
I/O
–
Oscillation terminal.
61
INH
I
L
Force the display to turn off
regardless of internal data. Serial
data can be input regardless of
whether it is "H" or "L".
62
CE
I
H
Chip enable. Serial data transfer
terminal. Connected to the
microprocessor.
63
CL
I
±
Synchronizing clock. Serial data
transfer terminal. Connected to
the microprocessor.
64
DI
I
–
Transfer data. Serial data transfer
terminal. Connected to the
microprocessor.