Rainbow Electronics HT49R70A-1 User Manual

Page 21

HT49R70A-1

Rev. 1.00

December 4, 2001

LCD driver output

The output number of the HT49R70A-1 LCD driver can

be 41

´2 or 41´3 or 40´4 by option (i.e., 1/2duty, 1/3duty

or 1/4duty). The bias type LCD driver can be

²R² type or

²C² type. If the ²R² bias type is selected, no external ca-
pacitor is required. If the

²C² bias type is selected, a ca-

pacitor mounted between C1 and C2 pins is needed.
The LCD driver bias voltage can be 1/2bias or 1/3bias
by option. If 1/2bias is selected, a capacitor mounted be-
tween V2 pin and ground is required. If 1/3bias is se-
lected, two capacitors are needed for V1 and V2 pins.
Refer to application diagram.

N o r m a l O p e r a t i o n M o d e :

D u r i n g a R e s e t P u l s e :

C O M 0 , C O M 1 , C O M 2

V L C D
1 / 2 V L C D

V S S
V L C D

1 / 2 V L C D

V S S

A l l L C D d r i v e r o u t p u t s

L C D s e g m e n t s o n C O M
0 , 1 , 2 s i d e s b e i n g u n l i t

C O M 0

C O M 1

C O M 2

O n l y L C D s e g m e n t s o n
C O M 0 s i d e b e i n g l i t

O n l y L C D s e g m e n t s o n
C O M 1 s i d e b e i n g l i t

O n l y L C D s e g m e n t s o n
C O M 2 s i d e b e i n g l i t

L C D s e g m e n t s o n
C O M 0 , 1 s i d e s b e i n g l i t

C O M 0 , 2 s i d e s b e i n g l i t

L C D s e g m e n t s o n

L C D s e g m e n t s o n
C O M 1 , 2 s i d e s b e i n g l i t

H a l t M o d e :

C O M 0 , 1 , 2 s i d e s b e i n g l i t

L C D s e g m e n t s o n

C O M 0 , C O M 1 , C O M 2

A l l L C D d r i v e r o u t p u t s

V L C D

1 / 2 V L C D
V S S
V L C D

1 / 2 V L C D

V S S
V L C D
1 / 2 V L C D

V S S

V L C D
1 / 2 V L C D
V S S

V L C D
1 / 2 V L C D

V S S

V L C D

1 / 2 V L C D

V S S
V L C D
1 / 2 V L C D

V S S
V L C D

1 / 2 V L C D

V S S

V L C D
1 / 2 V L C D

V S S

V L C D
1 / 2 V L C D
V S S
V D D

1 / 2 V L C D

V S S

N o t e : "

" O m i t t h e C O M 2 s i g n a l , i f t h e 1 / 2 d u t y L C D i s u s e d .

LCD driver output (1/3duty, 1/2bias, R/C type)