Reset Output

A µP’s reset input starts the µP in a known state.

Whenever the µP is in an unknown state, it should be

held in reset. The MAX814/MAX815/MAX816 assert reset

during power-up, power-down, or brownout conditions.

internal timer releases RESET after 200ms. RESET also

old (i.e., brownout condition). If brownout occurs in the

middle of a previously initiated reset, the internal timer

is reset and the output remains low for at least another

140ms after the brownout ends. On power-down, once

below 1V.

The MAX814 and MAX816 also offer active-high RESET

outputs. They are the inverse of the RESET outputs.

±1% Accuracy, Low-Power, +3V and +5V

µP Supervisory Circuits

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9

MAX814

RESET

GENERATOR

RESET THRESHOLD

POWER- FAIL THRESHOLD

60mV

1

150

µA

8

7

6

5

MR

RESET

RESET

LOW LINE

PFO

PFI

2

4

GND

3

MAX815

TIMEBASE

RESET THRESHOLD

POWER-FAIL THRESHOLD

150

µA

6

8

7

5

MR

WDO

RESET

PFO

WDI

PFI

2

1

4

GND

3

RESET

GENERATOR

WATCHDOG

TIMER

WATCHDOG

TRANSITION

DETECTOR

MAX816

RESET

GENERATOR

1.70V

1.70V

1

2

150

µA

8

7

5

MR

RESET

RESET

PFO

RESET IN

PFI

6

4

GND

3

Figure 4. MAX814 Block Diagram

Figure 5. MAX815 Block Diagram

Figure 6. MAX816 Block Diagram