Hex/Quad, Power-Supply Supervisory Circuits

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5

Pin Description (continued)

PIN

MAX6887

MAX6888

NAME

FUNCTION

55

MR

Manual Reset Input. Pull MR low to assert RESET. Connect MR to WDO to generate resets

when the watchdog timer expires. Leave MR unconnected or connect to DBP if unused. MR is

internally pulled up to BP through a 10µA current source.

66

MARGIN

Margin Input. When MARGIN is pulled low, RESET is held in its existing state independent of

subsequent changes in monitored input voltages or the watchdog timer expiration. MARGIN is

internally pulled up to BP through a 10µA current source. Leave MARGIN unconnected or

connect to BP if unused. MARGIN overrides MR if both are asserted at the same time.

7

7

WDI

Watchdog Timer Input. Logic input for the watchdog timer function. If WDI is not strobed with a

valid low-to-high or high-to-low transition within the selected watchdog timeout period, WDO

asserts. WDI is internally pulled down to GND through a 10µA current sink.

8

8

I.C.

Internal Connection. Leave unconnected.

99

10

10

BP

Bypass Voltage. The internally generated voltage at BP supplies power to internal logic and

output RESET. Connect a 1µF capacitor from BP to GND as close to the device as possible. Do

not use BP to supply power to external circuitry.

11

—

IN6

Input Voltage Detector 6. IN6 monitors both undervoltage and overvoltage conditions. See the

thresholds options (Tables 1 and 2) for available thresholds. IN6 cannot power the device. For

improved noise immunity, bypass IN6 to GND with a 0.1µF capacitor installed as close to the

device as possible.

12

—

IN5

Input Voltage Detector 5. IN5 monitors both undervoltage and overvoltage conditions. See the

thresholds options (Tables 1 and 2) for available thresholds. IN5 cannot power the device. For

improved noise immunity, bypass IN5 to GND with a 0.1µF capacitor installed as close to the

device as possible.

13

13

IN4

Input Voltage Detector 4. IN4 monitors both undervoltage and overvoltage conditions. See the

thresholds options (Tables 1 and 2) for available thresholds. Power the device through IN1–IN4

bypass IN4 to GND with a 0.1µF capacitor installed as close to the device as possible.

14

14

IN3

Input Voltage Detector 3. IN3 monitors both undervoltage and overvoltage conditions. See the

thresholds options (Tables 1 and 2) for available thresholds. Power the device through IN1–IN4

bypass IN3 to GND with a 0.1µF capacitor installed as close to the device as possible.

15

15

IN2

Input Voltage Detector 2. IN2 monitors both undervoltage and overvoltage conditions. See the

thresholds options (Tables 1 and 2) for available thresholds. Power the device through IN1–IN4

bypass IN2 to GND with a 0.1µF capacitor installed as close to the device as possible.

16

16

IN1

Input Voltage Detector 1. IN1 monitors both undervoltage and overvoltage conditions. See the

thresholds options (Tables 1 and 2) for available thresholds. Power the device through IN1–IN4

bypass IN1 to GND with a 0.1µF capacitor installed as close to the device as possible.

—

11, 12

N.C.

No Connection. Not internally connected.

——

EP

Exposed Paddle. Internally connected to GND. Connect EP to GND or leave unconnected.