Rainbow Electronics MAX6871 User Manual

Page 11

MAX6870/MAX6871

EEPROM-Programmable Hex/Quad

Power-Supply Sequencers/Supervisors with ADC

______________________________________________________________________________________

COMPARATORS

ADC

MUX

ADC

ADC REGISTERS

CONTROLLER

EEPROM

(USER AND

CONFIG)

OUTPUT

STAGES

LOGIC NETWORK

FOR PO_

WATCHDOG

TIMERS

GPI_

GPI_, MR,

MARGIN

PO_

IN_

SDA,

SCL

ANALOG
BLOCK

DIGITAL
BLOCK

SERIAL

INTERFACE

AUXIN_

Figure 1. Top Level Block Diagram

watchdog timer to clear on a combination of one GPI_
input and one programmable output, one of the GPI_
inputs only, or one of the programmable outputs only.
The initial and normal watchdog timeout periods are
independently programmable from 6.25ms to 102.4s.

A virtual diode-ORing scheme selects the input that pow-
ers the MAX6870/MAX6871. The MAX6870/MAX6871

derive power from IN1 if V

IN1

> +6.5V or from the highest

voltage on IN3–IN6 if V

IN1

< +2.7V. The power source

cannot be determined if +4V < V

IN1

< +6.5V and one

of V

IN3

through V

IN6

> +2.7V. The programmable out-

puts maintain the correct programmed logic state for
V

ABP

> V

UVLO

. One of IN3 through IN6 must be

greater than +2.7V or IN1 must be greater than +4V for
device operation.