M5295AL MITSUBISHI [Mitsubishi Electric Semiconductor], M5295AL Datasheet - Page 6

• Manufacturer Part Number: M5295AL
• Description: WATCHDOG TIMER
• Manufacturer: MITSUBISHI [Mitsubishi Electric Semiconductor]

APPLICATION EXAMPLE
1.When malfunction occurs due to noise or other related
2.To adjust detection voltage,add resistance of 15k
3.Set t
4.Input clock pulses to pin 1 via capacitor.To determine
OPERATION INSTRUCTIONS
trouble,connect capacitance of approximately 1000pF
between pin 5 and GND as well as pin 8 and GND to
stabilize operation.
or less to both Vcc and GND via adjusting pins.
(Set detection voltage to no less than 3V.)
110µs t
8.3µs t
10k
capacitance,refer to "Relationship between Input Pulse
Width and Input Capacitance Cin".
(2)Detection voltage 2(V
WD
R1 30k
CLOCK
R3
R4
RST
WD
and tRST(2) as shown below:
1
(2) 83ms
1.1s
5
2
51.2k
18.8k
3
RST1
(RESET)
TH
4
M5295AL
MCU/MPU
2(L))adjustment
1.24V
4
+
-
5
7
6
6
R
RST2
(HOLD)
7
L
VTH2(L)(V)
MITSUBISHI
8
To adjust detection voltage 2,determine external resistance
with the following equations:
3.5
4.6
13
10
7
5
4
ELECTRIC
Example of Backup Circuit with M5295AL
b. V
a. V
R3(k )
10.61
8.38
1
10
10
10
10
R3=
R4=
TH
TH
V
2
2(L)<4.6V(R4=5k )
DD
2(L)>4.6V(R3=10k )
R4(k )
0.93
1.26
1.99
3.24
RESET
OUTPUT
5
5
R0
R0
3
1
(Note)Set backup switching voltage to be more
1
M5295AL
-
-
4
1
VTH2(mV)
1
MITSUBISHI<Dig.Ana.INTERFACE>
16.3
16.3
16.3
16.3
17.2
14.1
100
M5295AL/P/FP
than or equal to backup supply voltage.
51.2k
18.8k
5
Backup switching voltage
Switching voltage calculation formula
1
1
V
TH
Detection voltage calculation formula
V
6
2(L)=
TH
V
R
R
2(L)=
TH
03
04
7
VTH(L)
R
R
=R3//51.2k
=R4//18.8k
2=
R3
R03+R04
03
04
=R3//51.2k
=R4//18.8k
WATCHDOG TIMER
R0=
R0=
8
R04
R03+R04
51.2k
R03
R04
(V
8.37kX1.24
V
BACKUP POWER SUPPLY
R4
TH
TH
X1.24
(
2(L)-1.24
2(L)-1.24)3.95k
X1.24(V)
X100(mV)
1.24
6
10K
TO SYSTEM
/ 8 )
3.5V
Vcc