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Rainbow Electronics MAX6871 User Manual

General description, Applications, Features

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General Description

The MAX6870/MAX6871 EEPROM-configurable, multi-
voltage supply sequencers/supervisors monitor several
voltage detector inputs, two auxiliary inputs, and four
general-purpose logic inputs. The MAX6870/MAX6871
feature programmable outputs for highly configurable
power-supply sequencing applications. The MAX6870
features six voltage detector inputs and eight program-
mable outputs, while the MAX6871 features four voltage
detector inputs and five programmable outputs. Manual
reset and margin disable inputs offer additional flexibility.

All voltage detectors offer two configurable thresholds
for undervoltage/overvoltage or dual undervoltage
detection. One high voltage input (IN1) provides detec-
tor threshold voltages from +2.5V to +13.2V in 50mV
increments, or from +1.25V to +7.625V in 25mV incre-
ments. A bipolar input (IN2) provides detector threshold
voltages from ±2.5V to ±15.25V in 50mV increments, or
from ±1.25V to ±7.625V in 25mV increments. Positive
inputs (IN3–IN6) provide detector threshold voltages
from +1V to +5.5V in 20mV increments, or from +0.5V
to +3.05V in 10mV increments.

Programmable output stages control power-supply
sequencing or system resets/interrupts. Programmable
output options include: active-high, active-low, open-
drain, weak pullup, push-pull, and charge pump.
Programmable timing delay blocks configure each output
to wait between 25µs and 1600ms before deasserting. A
fault register logs the condition that caused each output
to assert (undervoltage, overvoltage, manual reset, etc.).

An internal 10-bit ADC monitors the voltage detector
inputs, and two auxiliary inputs through a multiplexer
that automatically sequences through all inputs every
200ms. A SMBus

TM

-/I

2

C

TM

-compatible, serial data inter-

face programs and communicates with the configuration
EEPROM, the configuration registers, the internal 4kb
user EEPROM, the ADC registers, and the fault registers
of the MAX6870/MAX6871.

The MAX6870/MAX6871 are available in a 7mm x 7mm
x 0.8mm 32-pin thin QFN package and operate over
the extended -40°C to +85°C temperature range.

Applications

Telecommunications/Central Office Systems
Networking Systems
Servers/Workstations
Basestations
Storage Equipment
Multimicroprocessor/Voltage Systems

Features

Six (MAX6870) or Four (MAX6871) Configurable

Input Voltage Detectors

One High Voltage Input (+1.25V to +7.625V or

+2.5V to +13.2V Thresholds)

One Bipolar Voltage Input (±1.25V to ±7.625V

or ±2.5V to ±15.25V Thresholds)

Four (MAX6870) or Two (MAX6871) Positive

Voltage Inputs (+0.5V to +3.05V or +1V to
+5.5V Thresholds)

Four General-Purpose Logic Inputs
Two Configurable Watchdog Timers
Eight (MAX6870) or Five (MAX6871)

Programmable Outputs

Active-High, Active-Low, Open-Drain, Weak

Pullup, Push-Pull, Charge-Pump

Timing Delays from 25µs to 1600ms

10-Bit Internal ADC Monitors the Input Voltage

Detectors and Two Auxiliary Inputs

Margining Disable and Manual Reset Controls
Internal 1.25V Reference or External Reference

Input

4kb Internal User EEPROM

Endurance: 100,000 Erase/Write Cycles
Data Retention: 10 Years

I

2

C/SMBus-Compatible Serial

Configuration/Communication Interface

±1% Threshold Accuracy

MAX6870/MAX6871

EEPROM-Programmable Hex/Quad

Power-Supply Sequencers/Supervisors with ADC

________________________________________________________________ Maxim Integrated Products

1

Ordering Information

19-3384; Rev 1; 9/04

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.

EVALUATION KIT

AVAILABLE

Pin Configurations, Typical Operating Circuit, and Selector
Guide appear at end of data sheet.

PART

TEMP RANGE

PIN-
PACKAGE

PKG

CODE

MAX6870ETJ

-40°C to +85°C

32 Thin QFN

T3277-2

MAX6871ETJ

-40°C to +85°C

32 Thin QFN

T3277-2

SMBus is a trademark of Intel Corp.

I

2

C is a trademark of Philips Corp.

Purchase of I

2

C components from Maxim Integrated Products,

Inc., or one of its sublicensed Associated Companies, conveys
a license under the Philips I

2

C Patent Rights to use these com-

ponents in an I

2

C system, provided that the system conforms

to the I

2

C Standard Specification as defined by Philips.