PEDL9204-02
OKI Semiconductor
ML9204-xx
PIN DESCRIPTION
Pin
33 to 67
1 to 6
100 to
128
8 to 31
Symbol
SEGA1 to A35
SEGB1 to B35
O
VFD tube anode
electrode
Type
Connects to
Description
VFD tube anode electrode drive output.
Directly connected to fluorescent display tube and a
pull-down resistor is not necessary. I
OH
< –5 mA
VFD tube grid electrode drive output.
Directly connected to fluorescent display tube and a
pull-down resistor is not necessary. I
OH
< –25 mA
VFD tube anode electrode drive output.
Directly connected to fluorescent display tube and a
pull-down resistor is not necessary. I
OH
< –15 mA
V
DD
-L-GND are power supplies for internal logic.
V
COM
-D-GND are power supplies for driving VFD tube
grid.
V
COM
-D-GND are power supplies for driving VFD tube
anode.
Use the same power supply for L-GND and D-GND.
Serial data input-output (positive logic).
Data is input and output to sift register synchronized
with the rise of shift clock.
When Inputting data input from the LSB.
Shift clock input.
Serial data is shifted on the rising edge of
CP.
Chip select input.
Serial data transfer is disabled when
CS
pin is “H” level.
Output pin for interrupt signal to micro controller.
When depression or release of key matrix switch is
detected, key scanning starts and when 1 cycle is
completed, this pin becomes high level. Upon receiving
encoder type rotary switch input, this pin becomes high
level. The INT pin remains at high level until the key
scan stop mode is selected..
Encoder type rotary switch input pins.
All inputs possess chattering absorption function of
256us period.
Those inputs must be tied to ground when they are
not used.
Input pins for return signal from key matrix with built-in
pull-up resister.
When input is low level, the key matrix switch is
regarded as being pressed.
Dose not have chattering absorption function.
COM1 to 24
O
VFD tube grid
electrode
68
99
96
71
7,32
69,98
70,97
ADA
O
ADB
V
DD
L-GND
V
COM
V
SEG
D-GND
—
VFD tube anode
electrode
Power supply
94
DI/O
I/O
Micro controller
93
92
CP
CS
l
l
Micro controller
Micro controller
95
INT
O
Micro controller
85,86
87,88
89,90
A1,B1
A2,B2
A3,B3
l
Rotary switch
79 to 84
COL1
to 6
I
Key matrix
4/41