ha16117fpc Renesas Electronics Corporation., ha16117fpc Datasheet - Page 17

• Manufacturer Part Number: ha16117fpc
• Description: Cmos Watchdog Timer
• Manufacturer: Renesas Electronics Corporation.

Selection of External Constants
If the reset duration necessary for the MPU to operate reliably at power-on is known, there is a simple
procedure for selecting external constants, starting from the power-on reset time (t
Application Example
START
Battery
Decide reset
Select external
low time (t
constant C
Set power-on
reset time t
RL
R
regulator
)
0.01 F
ON
5 V
Figure 4 Procedure for Selecting External Constants
C
0.1 F
F
C
R
Decide reset-clock
Select external
off time (t
constants R
SW
Set reset high
time t
V
P-RUN
C
C
CC
RH
F
R
OFF
HA16117F
1
)
and R
2
GND
ACC
RES
Tadj
Select external
constant C
R
510 k
R
750 k
F
1
2
Check watchdog
frequency range
f
H
RES
V
HA16117F Series
ON
and f
CC
Microprocessor
).
L
system
PORT GND
External
constant
values
17