General Description

The MAX5023/MAX5024 high-voltage linear regulators

operate from a +6.5V to +65V input voltage and deliver

up to 150mA of output current. These devices consume

only 60µA of quiescent current with no load and with-

stand a -60V reverse-battery voltage at the input. The

MAX5023/MAX5024 include an active-low internal

microprocessor (µP) reset circuit that asserts when the

regulator output drops below the preset output voltage

threshold by 7.5% or 12.5%, depending on the device

selected. Both devices are available with a fixed +3.3V

or

+5V

output.

These

devices

are

short-

circuit protected and include thermal shutdown.

In addition to an enable input to turn on or off the regu-

lator, the MAX5023/MAX5024 include a HOLD input

that allows for the implementation of a self-holding

circuit without requiring external components. Setting

HOLD low after enabling the regulator, forces the regu-

lator to remain on even if EN is subsequently set low.

Releasing HOLD shuts down the regulator.

The MAX5023 includes a watchdog input that monitors a

pulse train from the µP and generates reset pulses if the

watchdog input remains high or low for a duration longer

than the 1.6s watchdog timeout period. The MAX5024

includes a SET input which, when connected to ground,

selects a preset output voltage of +3.3V (MAX5024S/

MAX5024T) or +5V (MAX5024L/MAX5024M). Set the

adjustable output voltage by connecting SET to the regu-

lator’s output through a resistive-divider network.

The MAX5023/MAX5024 operate over the automotive

temperature range (-40°C to +125°C) and are available in

a thermally enhanced, surface-mount 8-pin SO package.

Applications

Automotive

Fire/Smoke Alarms

Industrial

Telecom/Networking

Home Security

Features

o Wide Operating Input Voltage Range

+6.5V to +65V

o Thermally Enhanced 8-Pin SO Package Dissipates

1.5W

o Guaranteed 150mA Output Current

o 60µA No-Load Supply Current

o -60V Reverse-Battery Protection

o Preset +3.3V or +5.0V Output Voltage

o Thermal and Short-Circuit Protection

o Operate Over -40°C to +125°C Temperature Range

o Integrated µP Reset Circuit

o Watchdog Timer with 1.6s Timeout Period

(MAX5023)

o Regulator Enable and Hold Inputs Implement

Self-Holding Circuit

o SET Input for Adjustable Output Voltage

(MAX5024)

65V, Low-Quiescent-Current, High-Voltage Linear

Regulators with µP Reset and Watchdog Timer

________________________________________________________________ Maxim Integrated Products

1

N.C.

HOLD

RESET

1

2

8

7

OUT

WDI

EN

GND

IN

SO

TOP VIEW

3

4

6

5

MAX5023

N.C.

HOLD

RESET

1

2

8

7

OUT

SET

EN

GND

IN

SO

3

4

6

5

MAX5024

PART

TEMP RANGE

PIN-PACKAGE

MAX5023 _ ASA

-40°C to +125°C

8 SO

MAX5024 _ ASA

-40°C to +125°C

8 SO

Pin Configurations

Ordering Information

19-2619; Rev 0; 10/02

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.

Selector Guide and Typical Operating Circuit appear at end

of data sheet.

Note: These parts offer a choice of reset thresholds, reset

threshold tolerances, and regulator output voltages. From the

Selector Guide, insert the desired suffix letter into the blank to

complete the part number.