M30222 Datasheet, PDF (152/237 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

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Specifications in this manual are tentative and subject to change
MITSUBISHI MICROCOMPUTERS
M30222 Group
Rev. G
LCD Drive Control Circuit
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
LCD Drive Timing
The LCDCK timing frequency (LCD drive timing) is generated internally and the frame frequency can
be determined with the following equation. The LCDCK count source frequency is fC1 (same fre-
quency as XCIN) or f32 (divide-by-32 of XIN frequency). Figure 1.121 shows the LCD drive waveform
(1/2 bias). Figure 1.122 shows the LCD drive waveform (1/3 bias).
f(LCDCK)=
(frequency of count source for LCDCK)
16 X (LCD frame frequency count value + 1)
Frame frequency=
f(LCDCK)
duty ratio
Internal logic
LCDCK timing
1/4 duty
COM0
COM1
COM2
COM3
SEG0
Voltage level
VL3
VL2=VL1
VSS
VL3
VSS
OFF
ON
OFF
ON
COM3 COM2 COM1 COM0 COM3 COM2 COM1 COM0
1/3 duty
COM0
COM1
COM2
SEG0
ON
OFF
ON
OFF
ON
OFF
1/2 duty
COM0
COM2
COM1
COM0 COM2
COM1
COM0 COM2
COM0
COM1
SEG0
ON
OFF
ON
OFF
ON
OFF
ON
OFF
COM1 COM0 COM1 COM0 COM1 COM0 COM1 COM0
Fig. 1.121. LCD drive waveform (1/2 bias)
VL3
VL2=VL1
VSS
VL3
VSS
VL3
VL2=VL1
VSS
VL3
VSS
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