Kenwood TK-190 Service Manual page 21

2. D/A Converter : M62354GP (TX-RX Unit IC1)
2-1. Terminal connection
Do 1
2
LD
CLK 3
DI 4
Ao 5
1
Ao 6
2
NC 7
GND 8
2-2. Block diagram
V V Ao
CC DD 6
16 15 14
+ –
D-A
Ch6 Ch5
L
(6)
.......
Address
Decoder
12 bit Shift Register
1 2 3
Do LD CLK
2-3. Terminal function
Pin No. Symbol I/O
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.
SEMICONDUCTOR DATA
16 V
CC
15
V
DD
14 Ao
6
13
Ao
5
12 Ao
4
11 Ao
3
10
NC
9 A
SS
Ao Ao Ao V
5 4 3 SS
13 12 11 9
+ – + – + –
8 bit
D-A D-A R-2R+Segment
D-A converter
Ch4 Ch3
8 bit
L L
Latch
(6)
.....
8 bit
L
Latch
Ch1 Ch2
8 bit
D-A R-2R+Segment
D-A Converter
+ – + –
Buffer
OP amp
4 5 6 8
DI Ao Ao GND
1 2
Function
3. LCD Driver : LC75824W (Control unit IC101)
3-1. Block diagram
VDD1
Common
driver
VDD2
INH
Clock
OSC
Generator
VDD
VSS
3-2. Terminal function
Pin No. Name I/O Active
1~12 S1/P1~S12/P12 O
13~51 S13~S51
52~55 COM1~COM4 O
56 VDD –
57 VDD1 I
58 VDD2 I
59 VSS –
60 OSC I/O
61 INH I
62 CE I
63 CL I
64 DI I
TK-190
................... ........
Segment Driver & Latch
Shift Register
Address
Detector
Function
– Segment output for displaying
data transferred from serial data.
– Common driver output.
Frame frequency fo=(fosc/512)Hz
–
– Apply 2/3 the LCD drive bias
voltage from outside. If 1/2 the
bias is applied, connect to VDD2.
– Apply 1/3 the LCD drive bias
voltage from outside. If 1/2 the
bias is applied, connect to VDD1.
–
– Oscillation terminal.
L Force the display to turn off
regardless of internal data. Serial
data can be input regardless of
whether it is "H" or "L".
H Chip enable. Serial data transfer
terminal. Connected to the
microprocessor.
±
Synchronizing clock. Serial data
transfer terminal. Connected to
the microprocessor.
– Transfer data. Serial data transfer
terminal. Connected to the
microprocessor.
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