h8s-2158 Renesas Electronics Corporation., h8s-2158 Datasheet - Page 816

• Manufacturer Part Number: h8s-2158
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 26 Clock Pulse Generator
Table 26.3 External Clock Input Conditions
The oscillator and duty correction circuit have a function to adjust the waveform of the external
clock input that is input to the EXTAL pin. When a specified clock signal is input to the EXTAL
pin, internal clock signal output is determined after the external clock output stabilization delay
time (t
signal should be set to low to hold it in reset state. Table 26.4 shows the external clock output
stabilization delay time. Figure 26.6 shows the timing of the external clock output stabilization
delay time.
Rev. 3.00 Jan 25, 2006 page 764 of 872
REJ09B0286-0300
Item
External clock
input pulse width
low level
External clock
input pulse width
high level
External clock
rising time
External clock
falling time
Clock pulse width
low level
Clock pulse width
high level
DEXT
) has passed. As the clock signal output is not determined during the t
EXTAL
Symbol
t
t
t
t
t
t
EXL
EXH
EXr
EXf
CL
CH
t
EXr
Figure 26.5 External Clock Input Timing
VCC = 3.0 to 3.6 V
Min
15
15
—
—
0.4
0.4
t
EXH
Max
—
—
5
5
0.6
0.6
VCC = 2.7 to 3.6 V
Min
20
20
—
—
0.4
0.4
t
EXf
t
EXL
Max
—
—
5
5
0.6
0.6
V
CC
× 0.5
Unit
ns
ns
ns
ns
t
t
cyc
cyc
DEXT
cycle, a reset
Test
Conditions
Figure 26.5
Figure 29.4