HD44780U Datasheet, PDF (49/59 Pages) Hitachi Semiconductor – Dot Matrix Liquid Crystal Display Controller/Driver

HD44780U
AC Characteristics (V_CC = 2.7 to 4.5 V, T_a = –30 to +75°C*³)
Clock Characteristics
Item
Symbol Min Typ Max Unit Test Condition Note*
External External clock frequency f_cp
125 250 350 kHz
11
clock
External clock duty
Duty 45
50
55
%
operation
External clock rise time t_rcp
—
—
0.2
µs
External clock fall time
t _fcp
—
—
0.2
µs
R_f
Clock oscillation frequency f_OSC
190 270 350 kHz R_f = 75 kΩ,
12
oscillation
V_CC = 3 V
Note: * Refer to the Electrical Characteristics Notes section following these tables.
Bus Timing Characteristics
Write Operation
Item
Symbol Min
Typ
Enable cycle time
t _cycE
1000 —
Enable pulse width (high level)
PW_EH
450
—
Enable rise/fall time
t_Er, t_Ef
—
—
Address set-up time (RS, R/W to E) t_AS
60
—
Address hold time
t _AH
20
—
Data set-up time
t _DSW
195
—
Data hold time
t_H
10
—
Max
—
—
25
—
—
—
—
Unit
ns
Test Condition
Figure 25
Read Operation
Item
Symbol Min
Typ
Enable cycle time
t _cycE
1000 —
Enable pulse width (high level)
PW_EH
450
—
Enable rise/fall time
t_Er, t_Ef
—
—
Address set-up time (RS, R/W to E) t_AS
60
—
Address hold time
t _AH
20
—
Data delay time
t _DDR
—
—
Data hold time
t _DHR
5
—
Max
—
—
25
—
—
360
—
Unit
ns
Test Condition
Figure 26
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