LC450029PKB

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17

Display Control and the INH Pad

Since the LSI internal data (1/4 duty : the display data D1 to D208 and the control data, 1/3 duty : the display data D1 to

D159 and the control data) is undefined when power is first applied. Applications should set the INH pad low at the

same time as power is applied to turn off the display (This sets the S1 to S53 and COM1 to COM4 pads the VSS level.)

and during this period send serial data from the controller. The controller should then set the INH pad high after the data

transfer has completed. This procedure prevents meaningless display at power on. VDD and VDDI are connected with

the same power supply. The timing of turn on and turn off for VDD and VDDI should be same time.

(See from Figure 5 to Figure 8)

 1/4 duty

(Note) The wait time (t1) which power supply turn on should be 1ms or more.

The discharge time (t2) of LCD panel’s electric charge should be decided the optimum value according to the

characteristic of the LCD panel.

The switching time (tc) of INH should be 10

s or more.

[Figure 5]

 1/3 duty

(Note) The wait time (t1) which power supply turn on should be 1ms or more.

The discharge time (t2) of LCD panel’s electric charge should be decided the optimum value according to the

characteristic of the LCD panel.

The switching time (tc) of INH should be 10

s or more.

[Figure 6]

Initialization of display data

and control data

t2

CE

INH

VIL1

tc

VIL1

t1

VDD=VDDI

OFF (VSS level output)

ON

Update display data

OFF (VSS level output)

S1 to S53

COM1 to COM4

Initialization of display data

and control data

t2

CE

INH

VIL1

tc

VIL1

t1

VDD=VDDI

OFF (VSS level output)

ON

Update display data

OFF (VSS level output)

S1 to S53

COM1 to COM4