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PT6547 V1.2

- 13 -

January, 2006

LCD Driver IC with Key Input Function

PT6547

COMMAND 4: DISPLAY CONTROL COMMANDS

The Display Control Commands are used to Sleep Mode control and all segment off.

When bit 1 (b0) is set to “1”, the segment display state is “ON”; When bit 1 (b0) is set to “0”, the

segment display state is “OFF”. This “OFF” state is achieved by outputting segment “OFF” waveforms

from the segment output pins.

Bit 2 to 3 (b1 to b2) are switch between Normal and Sleep Mode. Set the key states of the KS1 to KS6

key scan outputs during key scan standby.

Bit 8 (b7) is given the value of “1” while bit 7 to bit 4 (b6 to b3) is given the value of “0”. Please refer to

the diagram below.

When power is turned on, the bit 3 to bit 1 (b2 to b0) are given the value of “0”.

MSB

LSB

1

0

0

0

0

b2 b1 b0

Segment all OFF control setting:

0: OFF

1: ON

Sleep Control setting:

Control Bit

Output pins state during

key scan standby

b2

b1

Mode

OSC

oscillator

Segment/Common

Output state

KS1 KS2 KS3 KS4 KS5 KS6

0

0

Normal Operating

Operating

“H” “H” “H” “H” “H” “H”

0

1

“L”

“L”

“L”

“L”

“L”

“H”

1

0

“L”

“L”

“L”

“L”

“H” “H”

1

1

Sleep

Stopped

“L”

“H” “H” “H” “H” “H” “H”

*Note: Assumes that SG75/KS1 and SG76/KS2 output pins are selected for key scan output.

SLEEP MODE

Sleep mode is set up by setting b2 or b1 in the control bit to “1”. The segment and common outputs will

all go low, and the oscillator on the OSC pin will stop (it will be started by a key press). This mode could

reduce power dissipation. This mode is cleared by sending control data with both b2 and b1 set to “0”.