PATENTED
Block Diagram
D is p la y R A M
HT1621/HT1621G
O S C O
O S C I
C S
R D
W R
D A T A
V D D
V S S
B Z
B Z
T o n e F re q u e n c y
G e n e ra to r
C o n
a n
T im
C ir c
tro l
d
in g
u it
C O M 0
L C D D r iv e r /
B ia s C ir c u it
C O M 3
S E G 0
S E G 3 1
V L C D
W a tc h d o g T im e r
a n d
T im e B a s e G e n e r a to r
IR Q
Note:
CS: Chip selection
BZ, BZ: Tone outputs
WR, RD, DATA: Serial interface
COM0~COM3, SEG0~SEG31: LCD outputs
IRQ: Time base or WDT overflow output
Pin Assignment
S E G 7
1
2
3
4
5
6
7
8
9
1 0
1 1
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
2 0
2 1
2 2
2 3
2 4
S E G 6
S E G 5
S E G 4
S E G 3
S E G 2
S E G 1
S E G 0
C S
R D
W R
D A T A
V S S
O S C O
O S C I
V L C D
V D D
IR Q
B Z
B Z
C O M 0
C O M 1
C O M 2
C O M 3
4 8
4 7
4 6
4 5
4 4
4 3
4 2
4 1
4 0
3 9
3 8
3 7
3 6
3 5
3 4
3 3
3 2
3 1
3 0
2 9
2 8
2 7
2 6
2 5
S E G 8
S E G 9
S E G 1 0
S E G 1 1
S E G 1 2
S E G 1
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G 1 3
S E G 1 4
S E G 1 5
S E G 1 6
S E G 1 7
S E G 1 8
S E G 1 9
S E G 2 0
S E G 2 1
S E G 2 2
S E G 2 3
S E G 2 4
C
S E G 2 5
S E G 2 6
S E G 2 7
S E G 2 8
S E G 2 9
S E G 3 0
S E G 3 1
C
C
V
D
C S
R D
W R
A T A
V S S
L C D
V D D
B Z
O M 0
O M 1
O M 2
1
2
3
4
5
6
7
8
9
1 0
1 1
1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0 2 1 2 2
4 4 4 3 4 2 4 1
4 0 3 9 3 8 3 7 3 6 3 5 3 4
3 3
3 2
3 1
3 0
S E G
S E G
S E
S E
S E
S E
S E
S E
S E
S E
S E
S E
1 1
1 0
G 9
G 8
G 7
G 6
G 5
G 4
G 3
G 2
G 1
4 7
4 6
4 5
4 4
4 3
4 2
4 1
4 0
3 9
3 8
3 7
G 0
4 8
1
2
3
4
5
6
7
8
9
1 0
1 1
1 2
1 3
0
H T 1 6 2 1
4 4 Q F P -B /L Q F P -A
2 9
2 8
2 7
2 6
2 5
2 4
2 3
1
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S G E
S E G
S E G
1 1
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
2 0
2 1
C S
R D
W R
D A T A
V S S
O S C O
O S C I
V L C D
V D D
IR Q
B Z
B Z
S E
S E
S E
S E
S E
S E
S E
S E
S E
S E
C O
G 2
G 2
G 2
G 2
G 2
G 2
G 2
G 2
G 3
G 3
M 3
1
0
9
8
7
6
5
4
3
2
2
3
4
5
6
7
8
9
0
3 6
3 5
3 4
3 3
3 2
3 1
3 0
2 9
2 8
2 7
2 6
2 5
H T 1 6 2 1 B
4 8 L Q F P -A
1 4
1 5
1 6
1 7
1 8
1 9
2 0
2 1
2 2
2 3
2 4
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S G E
S E G
S E G
S E G
S E G
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 9
2 0
2 1
2 2
2 3
N o te : * P le a s e n o te th a t in th e 4 8 - p in L Q F P p a c k a g e ,
th e S E G 2 7 a n d S E G 2 8 p in s a r e n o t in s e q u e n tia l o r d e r .
S E G
S E G
S E G
S E G
S E G
S E G
S E G
S E G
C O M
C O M
C O M
C O M
3 1
3
3 0
2 9
2 4
2 5
2 6
2 8
*
2 7
*
0
1
2
H T 1 6 2 1 B
4 8 S S O P -A
Rev. 2.90
2
November 9, 2010
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
