tWD values for different SET[1:0] logic levels when using Watchdog Time setting as option G = 100 msec. The

package pin out selected does not offer WD-EN pin.

Table 8-2. tWD Scaling with SET0 & SET1 Pins, WD-EN Pin Not Available

WATCHDOG TIME

SCALING SELECTION

tWD

SET[1:0] = 0b'00

SET[1:0] = 0b'01

SET[1:0] = 0b'10

SET[1:0] = 0b'11

A

100 msec

Watchdog disable

200 msec

400 msec

B

100 msec

Watchdog disable

400 msec

800 msec

C

100 msec

Watchdog disable

800 msec

1600 msec

D

100 msec

Watchdog disable

1600 msec

3200 msec

E

100 msec

Watchdog disable

3200 msec

6400 msec

F

100 msec

Watchdog disable

6400 msec

12800 msec

G

100 msec

Watchdog disable

12800 msec

25600 msec

Selected pinout option can offer WD-EN pin along with SET[1:0] pins. With this pinout, the WD-EN pin controls

watchdog enable and disable operation. The SET[1:0] = 0b'01 combination operates as SET[1:0] = 0b'00.

Make sure the tWD value with SETx multiplier does not exceed 640 sec. If a selection of timer and multiplier

results in tWD > 640 sec, the timer value will be restricted to 640 sec.

Figure 8-9 to Figure 8-11 diagrams show the timing behavior with respect to SETx status changes.

WDO

WDI

ttWDt

WD_EN = 1

ttWDt

ttWDt

ttWD X nt

SETx

ttWD X nt

ttWD X mt

ttWD X mt

WD multiplier = 1

WD multiplier = n

WD multiplier = m

Figure 8-9. Watchdog Behavior with SETx Pin Status

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TPS3435

SNVSCF7 – DECEMBER 2022

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