HD66765 Datasheet, PDF (58/71 Pages) Hitachi Semiconductor – 396-channel Segment Driver with Internal RAM for 4096-color Displays

HD66765
Grayscale Palette
The HD66765 incorporates a grayscale palette to simultaneously display 4,096 out of 13,824 possible
colors. The grayscales consist of sixteen five-bit palettes. The 24-stage grayscale levels can be selected
from the five-bit palette data.
In this palette, a pulse-width control system (PWM) is used to eliminate flicker in the LCD display. The
time over which the LCDs are switched on is adjusted according to the level and grayscales are displayed
so that flicker is reduced and grayscales are clearly displayed.
Graphics RAM (GRAM)
tion ^MSB
LSB
ifica ^{Display data R3 R2 R1 R0 G3 G2 G1 G0 B3 B2 B1 B0}
c ₄
pe ^{<RGB> Palette}
S "0000" PK04 PK03 PK02 PK01 PK03
y ^{"0001" PK14 PK13 PK12 PK11 RK13}
r _{"0010" PK24 PK23 PK22 PK21 PK23}
ina ^{"0011" PK34 PK33 PK32 PK31 PK33}
"0100" PK44 PK43 PK42 PK41 PK43
lim ^{"0101" PK54 PK53 PK52 PK51 PK53}
e^{"0110" PK64 PK63 PK62 PK61 PK63}
Pr ^{"0111" PK74 PK73 PK72 PK71 PK73}
4
4
"1000" PK84 PK83 PK82 PK81 PK80
"1001" PK94 PK93 PK92 PK91 RK90
"1010" PK104 PK103 PK102 PK101 PK100
"1011" PK114 PK113 PK112 PK111 PK110
"1100" PK124 PK123 PK122 PK121 PK120
"1101" PK134 PK133 PK132 PK131 PK130
"1110" PK144 PK143 PK142 PK141 PK140
"1111" PK154 PK153 PK152 PK151 PK150
5
5
5
24 grayscale ontrol
<R>
LCD driver
24 grayscale ontrol
<G>
LCD driver
24 grayscale ontrol
<B>
LCD driver
R
G
B
LCD
Figure 44 Grayscale Palette Control
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