µ PD160083
4. RELATIONSHIP BETWEEN INPUT DATA AND OUTPUT VOLTAGE VALUE
The µPD160083 incorporates a 8-bit D/A converter whose odd output pins and even output pins output respectively
gray scale voltages of differing polarity with respect to the LCD’s counter electrode (common electrode) voltage. The
D/A converter consists of ladder resistors and switches. The ladder resistors (r0 to r255) are designed so that the ratio
of LCD panel γ -compensated voltages to V0’-V255’ and V0”-V255” is almost equivalent, therefore, each resistance value
indicates figure 4−2. For the 2 sets of 9 γ -compensated power supplies, V0-V8 and V9-V17, respectively, input gray
scale voltages of the same polarity with respect to the common voltage
Figure 4−1 shows the relationship between the driving voltages such as liquid-crystal driving voltages VDD2, VSS2 and
0.5 VDD2, and γ -corrected voltages V0-V17 and the input data. Be sure to maintain the voltage relationships below.
VDD2 – 0.1 V ≥ V0 >V1 >V2 >V3 >V4 >V5 >V6 >V7 >V8 ≥ 0.5 VDD2
0.5 VDD2 ≥ V9 >V10 >V11 >V12 >V13 >V14 >V15 >V16 >V17 ≥ VSS2 + 0.1 V
Figures 4−2 shows γ -corrected voltages and ladder resistors ratio and figure 4−3 shows relationship between the
input data and the output voltage.
Figure 4−1. Relationship Between Input Data and γ -corrected Power Supply
0.1 V
VDD2
V0
V1
V2
V3
V4
V5
V6
V7
V8
0.5 VDD2
V9
V10
V11
V12
V13
V14
V15
V16
V17
0.1 V
VSS2
00 01 20
40
80
Input data (HEX.)
1
31
32
64
64
32
30
1
1
30
32
64
64
32
31
1
C0
E0 FE FF
6
Preliminary Product Information S16450EJ1V0PM00