General Description

The MAX6365–MAX6368 supervisory circuits simplify

power-supply monitoring, battery-backup control func-

tions, and memory write protection in microprocessor

(µP) systems. The circuits significantly improve the size,

accuracy, and reliability of modern systems with an ultra-

small integrated solution.

These devices perform four basic system functions:

up, power-down, and brownout conditions.

maintain data or low-power operation for CMOS

RAM, CMOS µPs, real-time clocks, and other digital

logic when the main supply fails.

3) Provide memory write protection through internal

chip-enable gating during supply or processor faults.

4) Include one of the following options: a manual reset

input (MAX6365), a watchdog timer function

(MAX6366), a battery-on output (MAX6367), or an

auxiliary user-adjustable reset input (MAX6368).

ages as low as 1.2V. The factory preset reset threshold

voltages range from 2.32V to 4.63V (see Ordering

Information). In addition, each part is offered in three

reset output versions: push-pull active low, open-drain

active low, or open-drain active high (see Selector

Guide). The MAX6365–MAX6368 are available in minia-

ture 8-pin SOT23 packages.

Applications

Critical µP/µC Power

Portable/Battery-

Monitoring

Powered Equipment

Fax Machines

Set-Top Boxes

Industrial Control

POS Equipment

Computers/Controllers

Features

o Precision Monitoring of +5.0V, +3.3V, +3.0V, and

+2.5V Power-Supply Voltages

o On-Board Gating of Chip-Enable Signals, 1.5ns

Propagation Delay

o Debounced Manual Reset Input (MAX6365)

o Watchdog Timer, 1.6s Timeout (MAX6366)

o Battery-On Output Indicator (MAX6367)

o Auxiliary User-Adjustable RESET IN (MAX6368)

o Low 10µA Quiescent Supply Current

o Three Available Output Structures

Push-Pull RESET

Open-Drain RESET

Open-Drain RESET

o RESET/RESET Valid Down to 1.2V Guaranteed

o Power-Supply Transient Immunity

o 150ms min Reset Timeout Period

o Miniature 8-Pin SOT23 Package

SOT23, Low-Power µP Supervisory Circuits

with Battery Backup and Chip-Enable Gating

________________________________________________________________ Maxim Integrated Products

1

OUT

MR

1

2

8

7

CE OUT

BATT

CE IN

GND

RESET, RESET

SOT23

TOP VIEW

3

4

6

5

MAX6365

Pin Configurations

19-1658; Rev 1; 6/01

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Ordering Information

*These parts offer a choice of reset threshold voltages. From the

Reset Threshold Ranges table, insert the desired threshold volt-

age code in the blank to complete the part number. SOT parts

come in tape-and-reel only and must be ordered in 2500-piece

increments. See Device Marking Codes for a complete parts list,

including SOT top marks and standard threshold versions. See

Selector Guide for a listing of device features.

Pin Configurations continued at end of data sheet.

Typical Operating Circuit appears at end of data sheet.

PART*

TEMP. RANGE

PIN-

PACKAGE

MAX6365LKA_ _-T

-40

°C to +85°C

8 SOT23-8

MAX6365PKA_ _-T

-40

°C to +85°C

8 SOT23-8

MAX6365HKA_ _-T

-40

°C to +85°C

8 SOT23-8

MAX6366LKA_ _-T

-40

°C to +85°C

8 SOT23-8

MAX6366PKA_ _-T

-40

°C to +85°C

8 SOT23-8

MAX6366HKA_ _-T

-40

°C to +85°C

8 SOT23-8

MAX6367LKA_ _-T

-40

°C to +85°C

8 SOT23-8

MAX6367PKA_ _-T

-40

°C to +85°C

8 SOT23-8

MAX6367HKA_ _-T

-40

°C to +85°C

8 SOT23-8

MAX6368LKA_ _-T

-40

°C to +85°C

8 SOT23-8

MAX6368PKA_ _-T

-40

°C to +85°C

8 SOT23-8

MAX6368HKA_ _-T

-40

°C to +85°C

8 SOT23-8