m5295a Renesas Electronics Corporation., m5295a Datasheet - Page 8

• Manufacturer Part Number: m5295a
• Description: Watchdog Timer
• Manufacturer: Renesas Electronics Corporation.

M5295AL/AP/AFP
Application Example
Notice for Use
1. When malfunction occurs due to noise or order related trouble, connect capacitance of approximately 1000 pF
2. To adjust detection voltage, add resistance of 15 kΩ or less to both V
3. Set t
4. Input clock pulses to pin (1) via capacitor. To determine capacitance, refer to “Relationship between input pulse
REJ03D0780-0200 Rev.2.00 Jun 15, 2007
Page 8 of 12
between pin (5) and GND as well as pin (8) and GND to stabilize operation.
voltage to no less than 3 V.)
width and input capacitance Cin”.
110 µs ≤ t
8.3 µs ≤ t
10 kΩ ≤ R
WD
and t
RST(2)
Backup switching voltage V
Note: Set backup switching voltage to be more than or equal to backup supply voltage.
RST(2)
WD
1
V
R
R
≤ 30 kΩ
TH2(L)
1
as shown below:
03
04
≤ 1.1 s
≤ 83 ms
= R
= R
=
2
3
4
R
// 51.2kΩ
// 18.8kΩ
Figure 9 Example of Backup Circuit with M5295AL
RESET output
03
R
Clock
3
+ R
04
1
04
M5295A
4
× 1.24 (V)
2
Figure 8 Application Example
TH2(L)
5
(RESET)
3
RST1
MCU/MPU
Switching voltage calculation formula
6
M5295A
4
7
5
R
3
8
6
R
(HOLD)
7
4
CC
RST2
and GND via adjusting pins. (Set detection
8
Backup power supply
10kΩ
To System
V
DD
3.5V
V
CC