ha16117fpc Renesas Electronics Corporation., ha16117fpc Datasheet - Page 16

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

HA16117F Series
Setting of RES Timing and Watchdog Frequency Range
Different MPUs have different RES timing requirements. The minimum reset time (t
on (rise of V
RES timing waveform parameters must be selected according to the MPU. With the HA16117F the timing
of the RES output and the watchdog frequency range can both be set by external constants (C
Item
Power-on reset time
Reset-clock off time
Reset low time
Reset high time
Watchdog frequency high
Watchdog frequency low
Notes: 1. K = R
Table 1
Item
t
t
t
t
t
Table 2
Item
f
f
16
ON
OFF
RL
RH
SL
H
L
(Hz)
(MHz)
(ms)
(ms)
(ms)
(ms)
(ms)
2. Variability of t
3. External constants should be selected with reference to the formulas in tables 1 and 2.
3.3 (M )
CC
Calculation of RES Output Timing
Calculation of Watchdog Frequency Range
) is 20 ms for some MPUs and 100 ms for others.
2
/ (R
1
C
Formula
400 ( )
1.99
0.5
Formula
Whichever is larger
+ R
1.7 (M )
K
500 ( )
F
OFF
t
( F), so C
OFF
2
31 ( A)
)
increases with increasing C
t
(ms)
ON
t
Symbol
t
t
t
t
f
f
RH
ON
OFF
RL
RH
H
L
1
(ms)
1.6 (V)
1
(ms)
C
C
R
C
F
F
( F)
F
( F)
15.8 ( A)
( F)
0.01 ( F) is recommended.
t
t
RH
RH
t
RH
Parameters
CR (pin 4)
(ms) + t
(ms)
(ms) + t
C
R
t
RL
( F)
(ms)
t
F
RL
RL
. The variability t
RL
(ms)
(ms)
(ms)
10
3
or
Notes
t
t
ON
RL
CF (pin 3)
and t
and t
t
*
OFF
2
1
(ms)
OFF
RH
OFF
can be set independently
is approximately
can be set independently
10
3
ON
) required at power-
K (pin 8) *
F
, C
R
, and K).
1