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7
KX-NT551RU/KX-NT551RU-B
4.2.
Circuit Operations
4.2.1.
LCD Circuit (Main LCD/Selflabeling LCD)
LCD data are output from pin E17 of IC502 to LCD module.
LCD contrast is set by electronic volume in LCD module.
+3.3V of the power supply voltage is pressurized about four/three times in the LCD module and used as LCD driving voltage
MainLCD : Approx 6.5v (MainLCD)
The driving voltage is observed between Pin 12 (V0) and Pin 13(XV0) of CN502 (Main LCD).
The driving voltage is observed between Pin 4 (V0) and Pin 3 (XV0) of CN505 (Self-Laeling LCD).
The back light for Self-Labeling is controlled by Q102.
LCD contrast is set by electronic volume in LCD module.
+3.3V of the power supply voltage is pressurized about four/three times in the LCD module and used as LCD driving voltage
MainLCD : Approx 6.5v (MainLCD)
The driving voltage is observed between Pin 12 (V0) and Pin 13(XV0) of CN502 (Main LCD).
The driving voltage is observed between Pin 4 (V0) and Pin 3 (XV0) of CN505 (Self-Laeling LCD).
The back light for Self-Labeling is controlled by Q102.
The lighting of the backlight is controlled by Q101 (Main LCD).
The PWM (Pulse Width Modulation) signal is output from IC502-U13 (Main), IC502-V13 (Self) pin and the brightness is changed
according to its duty ratio.
The PWM (Pulse Width Modulation) signal is output from IC502-U13 (Main), IC502-V13 (Self) pin and the brightness is changed
according to its duty ratio.
(Main LCD)
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