SSD1298 Crystalfontz America, Inc.,, SSD1298 Datasheet - Page 59

• Manufacturer Part Number: SSD1298
• Description: 240 Rgb X 320 Tft Lcd Controller Driver Integrated Power Circuit, Gate And Source Driver With Built-in Ram
• Manufacturer: Crystalfontz America, Inc.,

Grayscale voltage
9.3
This block outputs the reference voltage of the grayscale voltage. There are two ladder resistors including the variable
resistor and the 8 to 1 selector selecting voltage generated by the ladder resistor. The gamma registers control the
variable resistors and 8 to 1 selector resistors.
Variable Resistor
There are 3 types of the variable resistors that are for the gradient and amplitude adjustment. The resistance is set by the
resistor (PRP(N)0 / PRP(N)1) and (VRP(N)0 / VRP(N)1) as below.
8 to 1 selecter
In the 8 to 1 selector, a reference voltage VIN can be selected from the levels which are generated by the ladder resistors.
There are six types of reference voltage (VIN1 to VIN6) and totally 48 divided voltages can be selected in one ladder
resistor. Following figure explains the relationship between the micro-adjusting register and the selecting voltage.
SSD1298
PKP[2:0] VINP1 VINP2
Registor
000
001
010
011
100
101
110
111
V10
V11
V12
V13
V14
V15
V16
V17
V18
V19
V20
V21
V0
V1
V2
V3
V4
V5
V6
V7
V8
V9
Ladder Resistor / 8 to 1 selector
PRP(N)[0:1]
KVP1
KVP2 KVP10 KVP18 KVP26 KVP34 KVP42
KVP3 KVP11 KVP19 KVP27 KVP35 KVP43
KVP4 KVP12 KVP20 KVP28 KVP36 KVP44
KVP5 KVP13 KVP21 KVP29 KVP37 KVP45
KVP6 KVP14 KVP22 KVP30 KVP38 KVP46
KVP7 KVP15 KVP23 KVP31 KVP39 KVP47
KVP8 KVP16 KVP24 KVP32 KVP40 KVP48
000
001
010
011
100
101
110
111
VINP(N)0
VINP(N)1
V8+(V1-V8)*(30/48)
V8+(V1-V8)*(23/48)
V8+(V1-V8)*(16/48)
V8+(V1-V8)*(12/48)
V8+(V1-V8)*(8/48)
V8+(V1-V8)*(4/48)
VINP(N)2
V20+(V8-V20)*(22/24)
V20+(V8-V20)*(20/24)
V20+(V8-V20)*(18/24)
V20+(V8-V20)*(16/24)
V20+(V8-V20)*(14/24)
V20+(V8-V20)*(12/24)
V20+(V8-V20)*(10/24)
V20+(V8-V20)*(8/24)
V20+(V8-V20)*(6/24)
V20+(V8-V20)*(4/24)
V20+(V8-V20)*(2/24)
VINP(N)3
V43+(V20-V43)*(22/23)
KVP9
Rev 1.1
Postive polarity
Resistance
Formula
12R
16R
20R
24R
28R
Selected voltage
KVP17 KVP25 KVP33 KVP41
0R
4R
8R
VINP3
P 59/82
VINP4
Grayscale voltage
Mar 2008
VINP5
V22
V23
V24
V25
V26
V27
V28
V29
V30
V31
V32
V33
V34
V35
V36
V37
V38
V39
V40
V41
V42
V43
VRP(N)0
0000
0001
0010
1110
1111
VINP6
Step = 2R
V43+(V20-V43)*(21/23)
V43+(V20-V43)*(20/23)
V43+(V20-V43)*(19/23)
V43+(V20-V43)*(18/23)
V43+(V20-V43)*(17/23)
V43+(V20-V43)*(16/23)
V43+(V20-V43)*(15/23)
V43+(V20-V43)*(14/23)
V43+(V20-V43)*(13/23)
V43+(V20-V43)*(12/23)
V43+(V20-V43)*(11/23)
V43+(V20-V43)*(10/23)
V43+(V20-V43)*(9/23)
V43+(V20-V43)*(8/23)
V43+(V20-V43)*(7/23)
V43+(V20-V43)*(6/23)
V43+(V20-V43)*(5/23)
V43+(V20-V43)*(4/23)
V43+(V20-V43)*(3/23)
V43+(V20-V43)*(2/23)
V43+(V20-V43)*(1/23)
VINP(N)4
:
:
PKN[2:0]
Registor
Resistance
000
001
010
011
100
101
110
111
28R
30R
Formula
0R
2R
4R
VINN1
KVN1
KVN2
KVN3
KVN4
KVN5
KVN6
KVN7
KVN8
KVN10 KVN18 KVN26 KVN34 KVN42
KVN11 KVN19 KVN27 KVN35 KVN43
KVN12 KVN20 KVN28 KVN36 KVN44
KVN13 KVN21 KVN29 KVN37 KVN45
KVN14 KVN22 KVN30 KVN38 KVN46
KVN15 KVN23 KVN31 KVN39 KVN47
KVN16 KVN24 KVN32 KVN40 KVN48
VINN2
KVN9
Grayscale voltage
Negative polarity
VRP(N)1
Selected voltage
00000
00001
00010
11110
11111
KVN17 KVN25 KVN33 KVN41
VINN3
V44
V45
V46
V47
V48
V49
V50
V51
V52
V53
V54
V55
V56
V57
V58
V59
V60
V61
V62
V63
Step = 1R
VINN4
:
:
V55+(V43-V55)*(22/24)
V55+(V43-V55)*(20/24)
V55+(V43-V55)*(18/24)
V55+(V43-V55)*(16/24)
V55+(V43-V55)*(14/24)
V55+(V43-V55)*(12/24)
V55+(V43-V55)*(10/24)
V55+(V43-V55)*(8/24)
V55+(V43-V55)*(6/24)
V55+(V43-V55)*(4/24)
V55+(V43-V55)*(2/24)
VINP(N)5
V62+(V55-V62)*(44/48)
V62+(V55-V62)*(40/48)
V62+(V55-V62)*(36/48)
V62+(V55-V62)*(32/48)
V62+(V55-V62)*(25/48)
V62+(V55-V62)*(18/48)
VINP(N)6
VINP(N)7
Resistance
30R
31R
0R
1R
2R
VINN5
Formula
Solomon Systech
VINN6