hd66740 Renesas Electronics Corporation., hd66740 Datasheet - Page 83

• Manufacturer Part Number: hd66740
• Description: 112 X 80-dot Graphics Lcd Controller/driver - Hitachi Semiconductor
• Manufacturer: Renesas Electronics Corporation.

11. Applies to the internal oscillator operations using external oscillation resistor Rf (figure 44 and table
Table 28
12. Booster characteristics test circuits are shown in figure 45.
Rf
28).
(Quadruple boosting)
GND
Vcc
External
Resistance (Rf)
200 k
270 k
300 k
330 k
360 k
390 k
430 k
470 k
OSC1
OSC2
External Resistance Value and R-C Oscillation Frequency (Referential Data)
Vci
VLOUT
V
LCD
C1+
C1-
C2+
C2-
C3+
C3-
C4+
C4-
Since the oscillation frequency varies depending on the OSC1 and OSC2 pin
capacitance, the wiring length to these pins should be minimized.
R-C Oscillation Frequency: fosc
Vcc = 1.8 V
89 kHz
70 kHz
65 kHz
60 kHz
55 kHz
52 kHz
48 kHz
44 kHz
Figure 44
+
+
+
1 F
1 F
1 F
+
1 F
Figure 45
Vcc = 2.2 V
103kHz
80 kHz
73 kHz
68 kHz
62 kHz
58 kHz
53 kHz
48 kHz
Internal Oscillation
83
Booster
(Five-times boosting)
Vcc = 3.0 V
115 kHz
88 kHz
80 kHz
74 kHz
68 kHz
64 kHz
58 kHz
52 kHz
Vcc
GND
VLOUT
Vci
V
LCD
Vcc = 3.6 V
121 kHz
92 kHz
83 kHz
77 kHz
71 kHz
66 kHz
60 kHz
54 kHz
C1+
C1-
C2+
C2-
C3+
C3-
C4+
C4-
+
+
+
+
HD66740
+
1 F
1 F
1 F
1 F
1 F