Low-Voltage, Quad-/Hex-/Octal-Voltage

µP Supervisors

18

______________________________________________________________________________________

Detailed Description

The MAX16000–MAX16007 are low-voltage, quad-/hex-/

octal-voltage µP supervisors in small thin QFN and TSSOP

packages. These devices provide supervisory functions

for complex multivoltage systems. The MAX16000/

MAX16001/MAX16002 monitor four voltages, the

MAX16003/MAX16004/MAX16005 monitor six voltages,

and the MAX16006/MAX16007 monitor eight voltages.

The MAX16000/MAX16001/MAX16003/MAX16004/

MAX16006 offer independent outputs for each moni-

tored voltage. The MAX16001/MAX16002/MAX16004–

MAX16007 offer a reset output that asserts whenever

any of the monitored voltages fall below their respective

thresholds or the manual reset input is asserted. The

reset output remains asserted for the reset timeout after

all voltages are above their respective thresholds and

the manual reset input is deasserted. The minimum

reset timeout is internally set to 140ms or can be

adjusted with an external capacitor.

All open-drain outputs have internal 30µA pullups that

eliminate the need for external pullup resistors.

However, each output can be driven with an external

voltage up to 5.5V. Other features offered include a

manual reset input, a tolerance pin for selecting 5% or

10% input thresholds, and a margin enable function for

deasserting the outputs during margin testing.

The MAX16001/MAX16002/MAX16004–MAX16007 offer

a watchdog timer that asserts RESET or an indepen-

dent watchdog output (MAX16005) when the watchdog

timeout period (1.6s typ) is exceeded. The watchdog

timer can be disabled by floating the input.

Applications Information

Undervoltage-Detection Circuit

The open-drain outputs of the MAX16000–MAX16007

can be configured to detect an undervoltage condition.

Figure 6 shows a configuration where an LED turns on

when the comparator output is low, indicating an

undervoltage condition. These devices can also be

used in applications such as system supervisory moni-

monitoring (Figure 7).

Tolerance (TOL)

The MAX16000–MAX16007 feature a pin-selectable

threshold tolerance. Connect TOL to GND to select 5%

threshold tolerance.

Window Detection

A window detector circuit uses two auxiliary inputs in

the configuration shown in Figure 8. External resistors

set the two threshold voltages of the window detector

circuit. External logic gates create the OUT signal. The

window detection width is the difference between the

threshold voltages (Figure 9).

MAX16000

MAX16001

GND

IN1

V1

5V

V2

V3

V4

OUT1

IN2

IN3

IN4

OUT2

OUT3

OUT4

Figure 6. Quad Undervoltage Detector with LED Indicators

MAX16000

MAX16001

GND

D2

IN1

5V

OUT1

IN2

IN3

IN4

OUT2

OUT3

OUT4

D1

D3

D4