MITSUMI
System Reset (Built-in Watch Dog Timer) MM1099
Electrical Characteristics (AC)
Item
MM1099A
T
PI
MM1099B
T
CKW
T
CK
T
WD
T
WR
T
PR
V
CC
CK
Symbol
V
CC
(Except where noted otherwise, MM1096A : V
CC
=3.6V, Ta=25
°
C MM1096B : V
CC
=5.0V)
Min.
8
µS
8
or
3
20
C
T
=0.02µF
C
T
=0.02µF
50
1
50
100
2
100
2
2.0
0.2
150
3
150
10
4.0
1.0
µS
µS
mS
mS
mS
µS
µS
µS
Typ.
Max.
Units
Measurement conditions
3.6V
2.8V
5.0V
4.0V
V
CC
input
pulse width
CK input pulse width
CK input cycle
Watchdog timer
monitoring time 1
*
Reset time for
watchdog timer 2
*
Reset hold time for
power supply rise 3
*
C
T
=0.02µF, V
CC
----------------------------------------------------------------------
Output delay time from V
CC
4
*
T
PD
t
R
t
F
RESET pin, R
L
=10kΩ, C
L
=20pF
----------------------------------------------------------------------
Output rise time 5
*
Output fall time 5
*
RESET pin, R
L
=10kΩ, C
L
=20pF
----------------------------------------------------------------------
RESET pin, R
L
=10kΩ, C
L
=20pF
Notes :
1 The "monitoring time" means the time interval from the last pulse of the clock pulses for timer clear
(negative edge) to the output of the reset pulse. If the clock pulse is not input during this time interval, the
reset output will be given.
2 The "reset time" is no other than the reset pulse width, except when resetting the POWER ON.
3 The "reset hold time" is the time interval from the time point when V
CC
exceeds the detect (V
SH
) at the time
of Power On Reset (Power variation reset) to the reset release (RESET output "HIGH").
4 The "output delay time" means the time interval from when the supply voltage comes lower than the
detect voltage (V
SL
) to when comes the reset state (RESET output "Low").
5 The voltage range is 10 to 90% when measuring the output rise and fall times.
6 By varying the capacitance of C
T
, we can vary the watch dog timer monitoring time (T
WD
), the reset time at
the time of the watch dog timer (T
WR
), and the reset hold time at the time of power source rise (T
PR
). The
variable time can be expressed by the following formulas:
T
PR
(mS) . . 5000 C
T
(µF)
=
T
WD
(mS) . . 5000 C
T
(µF)
=
. 100 C
T
(µF)
T
WR
(mS) =
.
Example : When CT=0.02µF
.
T
PR
= 100mS
.
. 100mS
T
WD
=
.
. 2mS
T
WR
=
.
*
*
*
*
*
*
-------------------------------------------------
-------------------------------------------------
MITSUMI [ MITSUMI ELECTRONICS, CORP. ]
