h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 729

• Manufacturer Part Number: h8s-2138
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Table 23.4 External Clock Input Conditions
Table 23.5 shows the external clock output settling delay time, and figure 23.7 shows the external
clock output settling delay timing. The oscillator and duty adjustment circuit have a function for
adjusting the waveform of the external clock input at the EXTAL pin. When the prescribed clock
signal is input at the EXTAL pin, internal clock signal output is fixed after the elapse of the
external clock output settling delay time (t
t
Item
External clock
input low pulse
width
External clock
input high
pulse width
External clock
rise time
External clock
fall time
Clock low
pulse width
Clock high
pulse width
DEXT
period, the reset signal should be driven low to maintain the reset state.
EXTAL
Symbol Min
t
t
t
t
t
t
EXL
EXH
EXr
EXf
CL
CH
t
EXr
Figure 23.6 External Clock Input Timing
V
40
40
—
—
0.4
80
0.4
80
CC
= 2.7 to 5.5 V V
Max
—
—
10
10
0.6
—
0.6
—
t
EXH
DEXT
). As the clock signal output is not fixed during the
Min
20
20
—
—
0.4
80
0.4
80
CC
= 5.0 V ±10%
Rev. 4.00 Jun 06, 2006 page 675 of 1004
Max
—
—
5
5
0.6
—
0.6
—
t
EXf
t
EXL
Section 23 Clock Pulse Generator
Unit Test Conditions
ns
ns
ns
ns
t
ns
t
ns
cyc
cyc
Figure 23.6
< 5 MHz
< 5 MHz
V
CC
5 MHz Figure 25.5
5 MHz
REJ09B0301-0400
0.5