SED1330F Datasheet, PDF (116/148 Pages) List of Unclassifed Manufacturers – LCD Controller ICs

8.0 Description of Circuit Blocks
8.3 Oscillator Circuit
The SED1330F/1335F/1336F incorporates an oscil-
lator circuit. A stable oscillator can be constructed
simply by connecting an AT-cut crystal and two ca-
pacitors to OSC1 and OSC2, as shown in the figure
below. If the oscillator frequency is increased, C_D and
C_G should be decreased proportionally.
Note that the circuit board lines to OSC1 and OSC2
must be as short as possible to prevent wiring capaci-
tance from changing the oscillator frequency or in-
creasing the power consumption.
8.3 – 8.4
8.4 Status Flag
The SED1330F/1335F/1336F has a single bit status
flag.
D6: X line standby
D7
D0
X D6 X X X X X X X: Don’t care
Figure 76. Status flag
SED1335F/1336F
OSC1
C_G
OSC2
C_D
CD = 3 to 20 pF
C_G = 2 to 18 pF
Load impedance = 700 Ω (max)
Figure 75. Crystal oscillator
The D6 status flag is LOW (0) for the TC/R - C/R cycles
at the end of each line where the SED1330F/1335F/
1336F is not reading the display memory. The micro-
processor may use this period to update display
memory without affecting the display; however, it is
recommended that the display be turned off when
refreshing the whole display.
LP
XSCL
tTC/R
tm
tC/R
Figure 77. C/R to TC/R time difference
116 _{S-MOS Systems, Inc. • 2460 North First Street • San Jose, CA 95131 • Tel: [phone] • Fax: [phone]}