10

LED Control IC

W2RG012RN

■ Gradation Control

Designation of Gradation

Gradation is designated using a data length of 8 bits (256 gradations), 7 bits (128 gradations), or 4 bits (16 gradations). The 8-bit or 4-bit mode can

be selected using a word length bit in a communication command. In case of the 4-bit mode, the overall data length for communication can be

shortened, though only a small number of gradations can be designated. In case of SP-D7 mode in serial communication with address, the word

length is fixed at 7 bits, i.e., it is not designated.

The relationship between lighting gradation and output duty ratio is shown below;

Communication mode

Word length

Gradation number

Serial communication with address

(SP-D8)

8-bit mode

256

4-bit mode

16

Serial communication with address

(SP-D7)

---

128

Serial communication with address

(CE-D8)

8-bit mode

256

4-bit mode

16

8-bit mode

256

4-bit mode

16

Lighting Gradation vs. Output Duty Ratio

0 %

10 %

20 %

30 %

40 %

50 %

60 %

70 %

80 %

90 %

100 %

0

32

64

96 128 160 192 224

255

Lighting gradation

24×1

24×2

24×4

16×8

Lighting

gradation

(8-bit)

Lighting

gradation

(7-bit)

Lighting

gradation

(4-bit)

Matrix configuration

24x1

24x2

24x4

16x8

0

0

0

(Light-out)

(Light-out)

(Light-out)

(Light-out)

15

7

- - -

0.37%

0.18%

0.09%

0.05%

31

15

1

0.76%

0.38%

0.19%

0.09%

47

23

2

1.15%

0.57%

0.29%

0.14%

63

31

3

1.54%

0.77%

0.38%

0.19%

79

39

4

2.29%

1.15%

0.57%

0.29%

95

47

5

3.08%

1.54%

0.77%

0.38%

111

55

6

4.59%

2.29%

1.15%

0.57%

127

63

7

6.15%

3.08%

1.54%

0.77&

143

71

8

9.18%

4.59%

2.29%

1.15%

159

79

9

12.30%

6.15%

3.08%

1.54%

175

87

10

18.36%

9.18%

4.59%

2.29%

191

95

11

24.61%

12.30%

6.15%

3.08%

207

103

12

36.72%

18.36%

9.18%

4.59%

223

111

13

49.22%

24.61%

12.30%

6.15%

239

119

14

73.44%

36.72%

18.36%

9.18%

255

127

15

98.44%

49.22%

24.61%

12.30%

Lighting Gradation vs. Output Duty Ratio

(Representative Values Only)