Rainbow Electronics HD44780 - Manual (Page 59)

HD44780U
59
CL1
CL2
D
M
VOH2
VOH2
VOL2
t
ct
t
CWH
t
CWH
t
CSU
VOH2
t
CSU
t
CWL
t
ct
t
DH
t
SU
VOH2
t
DM
VOH2
VOL2
VOL2
Figure 27 Interface Timing with External Driver
V
CC
0.2 V
2.7 V/4.5 V* 2
0.2 V 0.2 V
t
rcc
t
OFF
*1
0.1 ms t
rcc
10 ms
≤ ≤
t
OFF
1 ms
≥
Notes: 1.
2.
3.
t
OFF
compensates for the power oscillation period caused by momentary power supply
oscillations.
Specified at 4.5 V for 5-V operation, and at 2.7 V for 3-V operation.
For if 4.5 V is not reached during 5-V operation, the internal reset circuit will not operate
normally.
In this case, the LSI must be initialized by software. (Refer to the Initializing by
Instruction section.)
Figure 28 Internal Power Supply Reset