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E LE CT R ICAL CHAR ACT E R IST ICS
7751 Group User’s Manual
15–9
Timer B input
(Count input in event counter mode)
15.5 Internal peripheral devices
Timer B input
(pulse period measurement mode)
Limits
Min.
80
40
40
160
80
80
Max.
ns
ns
ns
ns
ns
ns
Unit
Parameter
Symbol
TBi
IN
input cycle time (one edge count)
TBi
IN
input high-level pulse width (one edge count)
TBi
IN
input low-level pulse width (one edge count)
TBi
IN
input cycle time (both edges count)
TBi
IN
input high-level pulse width (both edges count)
TBi
IN
input low-level pulse width (both edges count)
Limits
t
c(TB)
t
w(TBH)
t
w(TBL)
TBi
IN
input cycle time
TBi
IN
input high-level pulse width
TBi
IN
input low-level pulse width
Min.
Max.
Unit
Symbol
Parameter
Data formula (Min.)
f(X
IN
)
≤
40 MHz
f(X
IN
)
≤
25 MHz
when
φ
divided by 2 selected as clock
source for peripheral devices
f(X
IN
)
≤
25 MHz
when
φ
selected as clock source for
peripheral devices
400
640
320
ns
16
10
9
IN
)
16
10
9
f(X
IN
)
8
10
9
f(X
IN
)
f(X
IN
)
≤
40 MHz
f(X
IN
)
≤
25 MHz
when
φ
divided by 2 selected as clock
source for peripheral devices
f(X
IN
)
≤
25 MHz
when
φ
selected as clock source for
peripheral devices
200
320
160
ns
8
10
9
f(X
IN
)
8
10
9
f(X
IN
)
4
10
9
f(X
IN
)
f(X
IN
)
≤
40 MHz
f(X
IN
)
≤
25 MHz
when
φ
divided by 2 selected as clock
source for peripheral devices
f(X
IN
)
≤
25 MHz
when
φ
selected as clock source for
peripheral devices
200
320
160
ns
8
10
9
f(X
IN
)
8
10
9
f(X
IN
)
4
10
9
f(X
IN
)
Notes 1:
TBi
IN
input cycle time must be 4 cycles or more of count source,
TBi
IN
input high-level pulse width must be 2 cycles or more of count source,
TBi
IN
input low-level pulse width must be 2 cycles or more of count source.
2:
The limits in the upper row of the table are the values when f(X
IN
) is 40 MHz and the count source is f
4
.
The limits in the middle row of the table are the values when f(X
IN
) is 25 MHz and the count source is f
4
.
The limits in the lower row of the table are the values when f(X
IN
) is 25 MHz and the count source is f
2
.
t
c(TB)
t
w(TBH)
t
w(TBL)
t
c(TB)
t
w(TBH)
t
w(TBL)