33.4.2 Watchdog Time-out Period Selection

The WDT time-out period is selected by postscaler dividers.

The WDT time-out period can be calculated using Equation 33-1, and WDT time-out period with window option can be calculated using Equation 33-2. The WDT period configurations for WDT time-out period are provided in Table 33-2.

Equation 33-1. Watchdog Timer Time-out Period

T_WTO = (N1) x (N2) x (T_CLK)

Where:

N1 = 32

N2 = Postscaler divider ratio (see Table 33-2)

T_CLK = WDT clock source

Table 33-2. WDT Period Configurations
RMPS[4:0]or SMPS[4:0]	Post-scale Ratio	Time-out Period
RMPS[4:0]or SMPS[4:0]	Post-scale Ratio	32 kHz	8 MHz	50 MHz
`00000`	1	1 ms	4 µs	640 ns
`00001`	2	2 ms	8 µs	1280 ns
`00010`	4	4 ms	16 µs	2.56 µs
`00011`	8	8 ms	32 µs	5.12 µs
`00100`	16	16 ms	64 µs	10.24 µs
`00101`	32	32 ms	128 µs	20.48 µs
`00110`	64	64 ms	256 µs	41.92 µs
`00111`	128	128 ms	512 µs	81.92 µs
`01000`	256	256 ms	1.02 ms	163.8 µs
`01001`	512	512 ms	2.05 ms	327.6 µs
`01010`	1024	1.024s	4.1 ms	655.4 µs
`01011`	2048	2.048s	8.2 ms	1310.8 µs
`01100`	4096	4.096s	16.4 ms	2.62 ms
`01101`	8192	8.192s	32.8ms	5.24 ms
`01110`	16384	16.384s	65.5 ms	10.48 ms
`01111`	32768	32.768s	131.1 ms	21 ms
`10000`	65536	00:01:05	262.1 ms	41.94 ms
`10001`	131072	00:02:11	524.3 ms	83.8 ms
`10010`	262144	00:04:22	1.05s	167.8 ms
`10011`	524288	00:08:44	2.1s	335.4 ms
`10100`	1048576	00:17:28	4.2s	671 ms
`10101`	2097152	00:34:57	8.4 s	1342.2 ms
`10110`	4194304	01:09:54	16.8s	2.68s
`10111`	8388608	02:19:48	33.5s	5.36s
`11000`	16777216	04:39:37	00:01:07	10.74s
`11001`	33554432	09:19:14	00:02:14	21.4s
`11010`	67108864	18:38:28	00:04:28	43s
`11011`	134217728	1day, 13:16:57	00:08:56	85.8s
`11100`	268435456	3days, 02:33:55	00:17:53	00:05:40
`11101`	536870912	6days, 05:07:50	00:35:47	00:11:24
`11110`	1073741824	12days, 10:15:41	01:11:35	00:22:52
`11111`	2147483648	24days, 20:31:23	02:23:10	00:45:48