ST7533 Sitronix Technology, ST7533 Datasheet - Page 17

• Manufacturer Part Number: ST7533
• Description: 33 x 96 Dot Matrix LCD Controller/Driver
• Manufacturer: Sitronix Technology

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ST7533
The Display Data Latch Circuit
The display data latch circuit is a latch that temporarily stores
the display data that is output to the liquid crystal
driver circuit from the display data RAM.
Because the display normal/reverse status, display ON/OFF
The Oscillator Circuit
This is a CR-type oscillator that produces the display clock.
The oscillator circuit is only enabled when M/S= “H” and CLS
= “H”.
Display Timing Generator Circuit
The display timing generator circuit generates the timing
signal to the line address circuit and the display data latch
circuit using the display clock. The display data is latched into
the display data latch circuit synchronized with the display
clock, and is output to the data driver output terminal.
Reading to the display data liquid crystal driver circuits is
completely independent of accesses to the display data RAM
by the MPU. Consequently, even if the display data RAM is
Two-frame alternating current drive waveform
Ver 1.0
COM0
COM1
SEGn
RAM
Data
CL
FR
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Figure 5
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status, and display all points ON/OFF commands control
only the data within the latch, they do not change
the data within the display data RAM itself.
When CLS = “L” the oscillation stops, and the external
clock is input through the CL terminal.
accessed asynchronously during liquid crystal display, there
i s a b s o l u t e l y n o a d v e r s e e f f e c t ( s u c h a s
flickering) on the display.
Moreover, the display timing generator circuit generates the
common timing and the liquid crystal alternating current
signal (FR) from the display clock. It generates a drive wave
form using a 2 frame alternating current drive method, as is
shown in Figure 5, for the liquid crystal drive circuit.
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6
2003/07/21
V
V
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V
V
V
V
V
V
V
V
V
DD
DD
DD
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5
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5