HT1621
A.C. Characteristics
Ta=25°C
Test Conditions
Conditions
Symbol
Parameter
Min.
Typ.
Max. Unit
VDD
¾
fSYS1
fSYS2
fSYS3
System Clock
System Clock
System Clock
On-chip RC oscillator
Crystal oscillator
256
32.768
256
kHz
kHz
kHz
Hz
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
External clock source
On-chip RC oscillator
Crystal oscillator
¾
¾
f
f
SYS1/1024
¾
¾
fLCD
fSYS2/128
LCD Clock
Hz
¾
¾
SYS3/1024
External clock source
n: Number of COM
Hz
¾
¾
tCOM
n/fLCD
¾
LCD Common Period
s
¾
¾
3V
5V
3V
5V
¾
150
300
75
150
¾
kHz
kHz
kHz
kHz
kHz
fCLK1
Serial Data Clock (WR pin)
Duty cycle 50%
Duty cycle 50%
¾
¾
fCLK2
Serial Data Clock (RD pin)
Tone Frequency
¾
fTONE
tCS
On-chip RC oscillator
CS
2.0 or 4.0
250
Serial Interface Reset Pulse
Width (Figure 3)
ns
¾
¾
¾
Write mode
Read mode
Write mode
Read mode
3.34
6.67
1.67
3.34
¾
¾
¾
¾
¾
¾
¾
¾
3V
ms
WR, RD Input Pulse Width
(Figure 1)
tCLK
5V
ms
Rise/Fall Time Serial Data
Clock Width (Figure 1)
tr, tf
120
120
120
100
100
ns
ns
ns
ns
ns
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
¾
Setup Time for DATA to WR,
RD Clock Width (Figure 2)
tsu
Hold Time for DATA to WR, RD
Clock Width (Figure 2)
th
Setup Time for CS to WR, RD
Clock Width (Figure 3)
tsu1
Hold Time for CS to WR, RD
Clock Width (Figure 3)
th1
V
a
l
i
d
D
a
t
a
t
f
t
r
V
G
D
D
V
G
D
D
9
0
%
W
R
,
R
D
D
B
5
0
%
5
0
%
N
D
C
l
o
c
k
N
D
1
0
%
t
S
U
t
h
t
C L K
t
C L K
V
G
D
D
W
R
,
R
D
5
0
%
Figure 1
C
l
o
c
k
N
D
Figure 2
t
C S
V
G
D
D
5
0
%
C
S
N
D
t
h 1
t
S U 1
V
G
D
D
W
R
,
R
D
5
0
%
C
l
o
c
k
N
D
F
i
r
s
t
C
l
o
c
k
L
a
s
t
C
l
o
c
k
Figure 3
Rev. 1.30
6
August 6, 2003
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
