Dual/Triple Ultra-Low-Voltage SOT23 µP

Supervisory Circuits

8

_______________________________________________________________________________________

Pin Description (continued)

PIN

MAX6715/

MAX6716

MAX6717/

MAX6718

MAX6719/

MAX6720

MAX6721/

MAX6722

MAX6723/

MAX6724

MAX6725/

MAX6726

MAX6727

MAX6728/

MAX6729

NAME

FUNCTION

——

—5

3333

WDI

Watchdog Input. If WDI

remains high or low for

longer than the watchdog

timeout period, the

internal watchdog timer

runs out and the reset

output asserts for the

reset timeout period. The

internal watchdog timer

clears whenever a reset

is asserted or WDI sees a

rising or falling edge. The

watchdog has a long

timeout period (35s min)

after each reset event

and a short timeout

period (1.12s min) after

the first valid WDI

transition.

——

5

—

577

—

RSTIN

Undervoltage Reset

Comparator Input. High-

impedance input for

adjustable reset monitor.

The reset output is

asserted when RSTIN falls

below the 0.626V internal

reference voltage. Set the

monitored voltage reset

threshold with an external

resistor-divider network.

——

———

——

7

PFI

Power-Fail Voltage

Monitor Input. High-

impedance input for

internal power-fail monitor

comparator. Connect PFI

to an external resistor-

divider network to set the

power-fail threshold

voltage (0.626V typical

internal reference

voltage). Connect to

not used.