S-19400 Datasheet, PDF (21/36 Pages) Seiko Instruments Inc – Watchdog operation voltage range

FOR AUTOMOTIVE 125°C OPERATION LOW CURRENT CONSUMPTION WATCHDOG TIMER WITH RESET FUNCTION
Rev.2.1_00
S-19400/19401 Series
6. 3 Double pulse detection due to both rising and falling edges detection
(S-1940xCxxA, S-1940xFxxA, S-1940xIxxA, S-1940xLxxA)
The double pulse is detected only when edges are input in order of rising and falling.
6. 3. 1 When edges are input to WDI pin in order of rising and falling
VDD
CPOR
CWDT
WDI
12 34
1 234
1 234
1 2 3 4 5 6 7 8 9 10 11
Counter reset at the1st edge
Output "H" → "L" at the 2nd edge
W / T "L"
(S-19400 only)
WEN
(Active "H")
WDO
RST
(S-19401 only)
Figure 36 Double Pulse Detection
6. 3. 2 When edges are input to WDI pin in order of falling and rising
VDD
CPOR
CWDT
WDI
1234
1 234
1 234 1 234
29 30 31 32
Counter reset at the 1st edge
Only counter reset at the 2nd edge
W / T "L"
(S-19400 only)
WEN
(Active "H")
WDO
RST
(S-19401 only)
Figure 37 Double Pulse Non-detection
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