MSM6555B-xx

¡ Semiconductor

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• 9D/17D (1/9Duty/1/17Duty)

This is a duty setting pin where "H" is defined as 1/9 duty and "L" as 1/17 duty. Select the level

in conformity to the panel used.

In the case of 1/17 duty, the Common outputs C10 to C16 must be kept open.

• 32K/EXT (32K x’tal osc/External clock)

This is an input pin used to set up the type of logic source oscillation.

32K/EXT = "H" : In this setting, 32.768 kHz is used for source oscillation frequency. The

oscillation feedback resistor (approx. 4 MW) is formed in the IC, and the external 32.768 kHz

crystal and oscillating capacitors are connected to the XT and XT, thereby forming the

oscillator circuit. When the source oscillation clock is input from outside, it is put into the XT,

and XT is kept open.

32K/EXT = "L" : This is used to input the source oscillation clock of about n-th power (n=1 to

4) of 2 of 32kHz.

Conforming to the command SF setting, the external source oscillation frequency is divided

into 1/2 to 1/16 in the IC and is used as source oscillation frequency in the IC. The XT is kept

open. Æ See SF command.

• TEST

This is a pin used for test in our company. This pin is kept open for the user.

• XT, XT

These are pins for 32.768 kHz crystal-controlled oscillator circuit formation and external

source oscillation input. XT is kept open, when the souce oscillation clock is input from

outside.

• C1 to C17, S1 to S80 (COMMON 1 to 17, SEGMENT 1 to 80)

These are output pins connected to the LCD panel. Alternation is provided by reserving the

frame. During the 1/9 duty operation, C1 to C9 are used with C10 to C17 kept open.

Æ See "Relation between Display Screen and Common and Segment Outputs".

These are pins to connect the capacitor to double the battery voltage. They are connected with

the capacitor of 0.1 mF.