Applications Information

In addition to issuing a reset to the µP during power-up,

power-down, and brownout conditions, the MAX6467/

MAX6468 are relatively immune to short-duration falling

Characteristics section shows the Maximum Transient

MAX6468 do not generate a reset pulse. This graph was

above the actual reset threshold and ending below the

The graph indicates the typical maximum pulse width a

pulse. As the magnitude of the transient increases (goes

farther below the reset threshold), the maximum allowable

pulse width decreases. A 0.1µF bypass capacitor from

Ensuring a Valid RESET Output Down

The MAX6467/MAX6468 guarantee proper operation

active-low outputs (MAX6468 only, Figure 3) ensures

that RESET remains valid while the RESET output can

no longer sink current. This scheme does not work with

the open-drain outputs of the MAX6467. Ensure that the

resistor value used does not overload the RESET output

cations, use 100k

Ω to 1MΩ.

Microprocessor Supervisory Reset Circuits

with Edge-Triggered, One-Shot Manual Reset

6

_______________________________________________________________________________________

RESET TIMEOUT SUFFIX

(min/max) (ms)

MR TIMEOUT PERIOD

(min/max) (ms)

MR RISING DEBOUNCE PERIOD

(min/max) (ms)

D3

150/300

150/300

150/300

D7

1200/2400

150/300

150/300

Reset Timeout Delay*

*Additional reset timeout options may be available. Contact factory for availability.

MAX6468

GND

RESET

R1

100k

Ω

Chip Information

TRANSISTOR COUNT: 748

PROCESS: BiCMOS

1.5k

Ω

MR ONE-SHOT/

DEBOUNCE

RESET

TIMEOUT

PERIOD

RESET

OUTPUT

1.23V

MR

RESET

GND

MAX6467

MAX6468

Figure 2. Functional Diagram