HT1350
Pad Description
Internal
Connection
Pad No
Pad Name I/O
Descriptions
1
TEST2
I/O
I/O
O
For IC test only
For IC test only
Oscillator output
Oscillator input
¾
2
TEST1
¾
3
OSC2
¾
4
OSC1
I
¾
CMOS
NMOS
*
5~18
OUT17~OUT4
O
Display data output pads for segments
Display data output pads for commons
19~21 COM3~COM1
22 CP3
23~24 CP2~CP1
O
O
Bias supply voltage pad for driving the LCD panel
LCD bias supply voltage control pads
O
*
CMOS
Pull-high
25
26
27
STEP
I
I
I
Step sensor input pad
CMOS
Pull-high
WALK/RUN
AUTO/MANU
Walk/Run mode manual set pad
Auto detection/Manual set selection pad
CMOS
Pull-high
28
29
30
VDD
TEST3
VSS
I
I/O
I
Positive power supply
For IC test only
¾
¾
¾
Negative power supply (GND)
CMOS
Pull-high
31
32
MODE
RESET
O
O
LCD display mode selection
System reset pad
CMOS
Pull-high
Approximate internal connection circuits
N
T
M
O
S
O
U
T
C
M
O
S
I
N
C
M
O
S
O
U
C
P
1
~
C
P
3
O
S
C
I
L
L
A
T
O
R
(
F
o
r
C
O
M
1
~
C
O
M
3
)
P
u
l
l
-
h
i
g
h
V
D
D
V
D
D
C
C
P
P
1
2
C
P
3
V
D
D
C
O
M
1
~
C
O
M
3
V
S
S
O
S
C
1
O
S
C
2
3
June 28, 1999
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
