Table of Contents
Advertisement
LCD Driver
The LCD driver is also used as an I/O port, and it allows a maximum of 72 segments to turn on. When the LCD driver is
enabled, I/O port 10 is switched to COM1 to COM4 pins and I/O port 12 is switched to S1 to S4 pins. Each of the 14 pins
of I/O ports 13, 14, 15 and 16 can be set to segment pin output.
The driving method of the LCD driver can be selected from 1/4 duty, 1/2 bias (frame frequency 62.5 Hz) and 1/3 bias
drive (frame frequency 125 Hz).
The LCD driver is built-in the constant voltage for display (V
increases the display voltage. The LCD driver ensures a stable LCD display; even if the supply voltage fluctuates. (→ Refer
to the section on the CD driver doubler circuit.)
In the 1/2 bias mode, the LCD driver provides common output at three potentials V
provides segment output at two potentials V
segment outputs at four potentials V
1. LCD Driver Ports
LCD driver control
LCD ドライバコントロール
Y1
DISP
φL17
OFF
φL/K1A
Y1
Y2
Y4
Y8
SEL1
SEL2
SEL4
SEL8
Data select
データセレクト
φL13(データポート4)
φL13 (Data port 4)
Y1
Y2
COM1 COM2 COM3 COM4
(4)
(5)
(6)
COM1 COM2 COM3 COM4
(F)
セグメント出力とI/Oポートの切り替え
Note:
Segment data controls the segments on/off corresponding to the common and segment outputs.
, GND. In the 1/3 bias mode, the LCD driver provides common and
LCD
× 2/3, V
, V
LCD
LCD
Y2
Y4
Y8
LCD
BIAS
*
OFF
Selection of LCD drive method
LCD ドライブ方式選択
LCD off control bit
LCD オフ制御ビット
LCD 表示オフ制御ビット
LCD display off control bit
Y4
Y8
(0)
Ｓ１
Ｓ２
Ｓ３
Ｓ１２
Switching between the segment
output and I/O port
0:I/Oポート
0: I/O port
1:セグメント出力
1: Segment output
= 1.5 V) and the doubler circuit (V
EE
× 1/3 and GND.
LCD
0: 1/2 bias
0：1/2 バイアス
1：1/3 バイアス
1: 1/3 bias
0: LCD driver
0：LCD ドライバ
1: I/O port
1：I/O ポート
0：設定データ出力
0: Set data output
1：オフデータ出力
1: Off data output
φL14 (Data port 5)
φL14(データポート5)
Y1
Y2
Y4
Y8
COM1 COM2 COM3 COM4
Ｓ１３
(1)
Ｓ１４
(2)
Ｓ１５
(3)
Ｓ１６
(4)
Ｓ１７
(5)
Ｓ１８
Segment select
セグメントセレクト
(C)
Ｓ５
Ｓ６
(D)
Ｓ９
Ｓ１０
(E)
Ｓ１３
Ｓ１４
(F)
Ｓ１５
Ｓ１６
92
TC9349AFG
= 3.0 V) that
LCD
× 1/2 and GND, and
, V
LCD
LCD
Segment data
セグメントデータ
0: Turn off
０： 消灯
1: Turn on
１： 点灯
Ｓ７
Ｓ８
Ｓ１１
Ｓ１２
＊
＊
Ｓ１７
Ｓ１８
2006-02-24
Advertisement
Table of Contents
