HT1647(2000) 查看數據表（PDF） - Holtek Semiconductor
零件编号
产品描述 (功能)
生产厂家
HT1647 Datasheet PDF : 24 Pages
| |||
Display memory - RAM structure
The static display RAM is organized into 512´4
bits and stores the display data. Two bits of
RAM map to Lad¢s one pixel and decide
whether 4-level gray scale or 4-color display
SEG 0
SEG 1
SEG 2
SEG 3
C O M 15
C O M 14
7
15
23
31
HT1647
concurrently. The contents of the RAM are di-
rectly mapped to the contents of the LCD
driver. Data in the RAM can be accessed by the
READ, WRITE and READ-MODIFY-WRITE
commands. The following is a mapping from
the RAM to the LCD patterns.
COM 1
COM 0
0
8
16
24
A d d r e s s 9 B its
(A 8 , A 7 , ...., A 0 )
S E G 63
511
504
A ddr
D3
D2
D1
D 0 D a ta
A ddr
D3
D2
D1
D 0 D a ta
D a ta 4 B its
(D 3 , D 2 , D 1 , D 0 )
: T w o b its o f R A M m a p to L C D 's o n e p ix e l a n d d e c id e 4 - le v e l g r a y s c a le
o r 4 - c o lo r d is p la y c o n c u r r e n tly .
Display memory - RAM structure
Gray scale level decision
HT1647 uses PWM technique to provide 4-level
gray scale display. Two bits of RAM data code
((D3, D2) or (D1, D0)) decide one pixel level of
LCDs, level 1~level 4 dividedly. Every level
must be defined as one kind of gray scale by PWM
data (namely B4~B0) previously.
RAM data code Choice Gray Scale
(D3, D2) or (D1, D0)
Level
(1, 1)
Level 1
(1, 0)
Level 2
(0, 1)
Level 3
(0, 0)
Level 4
RAM data defined gray scale level
Frame frequency
HT1647 provides two kinds frame frequency op-
tion by command code, 89Hz and 170Hz respec-
tively. FRAME 89Hz provides 89Hz frame
frequency and active segment signal width can be
divided into 24 sections concurrently. FRAME
170Hz provides 170Hz frame frequency and ac-
tive segment signal width can be divided into 13
sections concurrently. The 24 sections display a
particularly gray scale more than the 13 sections
by PWM data. The default is FRAME 89Hz.
Gray scale display
If the user choose 89Hz frame frequency, a max.
of 24 sections can be programmed to suit a sat-
isfactory gray scale in every level. Similarly, if
the user choose 170Hz frame frequency, a max.
of 13 sections can be programmed to suit a satis-
10
April 21, 2000
Share Link: 