General Description

The MAX6791–MAX6796 ultra-low-quiescent-current,

single-/dual-output linear regulators are ideal for auto-

motive applications. The devices offer a wide 5V to 72V

operating input range, allowing them to withstand auto-

motive load-dump conditions while consuming only

68µA. The MAX6791–MAX6794 are dual-output regula-

tors capable of supplying up to 150mA per output. The

MAX6795/MAX6796 offer a single output capable of

delivering up to 300mA. These devices offer standard

output-voltage options (5V, 3.3V, 2.5V, or 1.8V) and can

be adjusted to any voltage from 1.8V to 11V. The

MAX6791–MAX6794 also offer a fixed 5V output.

All devices feature a push-pull or open-drain, active-low

RESET output with a fixed output reset threshold that is

92.5%/87.5% of the regulator output OUT/OUT1. The

reset output asserts low when OUT/OUT1 drops below

the reset threshold and remains low for the fixed or

capacitor-adjustable reset timeout period after

OUT/OUT1 exceeds the reset threshold.

The MAX6791–MAX6796 provide a watchdog input that

monitors a pulse train from the microprocessor (µP) and

generates reset pulses if the watchdog input remains

high or low for a duration longer than the watchdog

timeout period. All devices are available with either a

fixed watchdog timeout period of 280ms (min) or a peri-

od adjustable with an external capacitor. The

MAX6791/MAX6792 feature a windowed watchdog

timeout period with selectable window ratio. The watch-

dog feature can be disabled.

The MAX6791–MAX6794 provide dual enable inputs

(ENABLE1 and ENABLE2) that control each regulator

independently. The single-output MAX6795/MAX6796

feature one enable input (ENABLE).

All devices include a hold input (HOLD) that aids the

implementation of a self-holding circuit without requir-

ing external components. Once the regulator is

enabled, setting HOLD low forces the regulator to

remain on even if ENABLE/ENABLE1 is subsequently

set low. Releasing HOLD shuts down the regulator.

The MAX6791–MAX6796 are available in a small, ther-

mally enhanced TQFN package. The 5mm x 5mm

package dissipates up to 2.7W, supporting continuous

regulator operation during high ambient temperatures,

high battery voltage, and high load-current conditions.

The MAX6791–MAX6796 are specified for a -40°C to

+125°C operating temperature range.

Applications

Automotive

Features

♦ Low 68µA Quiescent Current

♦ Wide 5V to 72V Supply Voltage Range

♦ Output Current

Single Output Up to 300mA

Dual Outputs Up to 150mA per Output

♦ Low Dropout Voltage

420mV (typ) at 100mA (Single)

840mV (typ) at 100mA (Dual)

♦ Fixed Output-Voltage Options: 5V, 3.3V, 2.5V,

1.8V, or Adjustable Output (from 1.8V to 11V)

♦ ENABLE and HOLD Functionality

♦ RESET Output: Open Drain or Push-Pull

♦ Internally Fixed (35µs, 3.125ms, 12.5ms, 50ms, or

200ms) or Capacitor-Adjustable Reset Timeout

Periods

♦ Internally Fixed or Capacitor-Adjustable

Watchdog Timeout Periods

♦ Windowed (Minimum/Maximum) Watchdog Timer

Options (MAX6791/MAX6792)

♦ Watchdog Disable Feature

♦ Thermal, Short-Circuit, and Output Overvoltage

Protection

♦ Fully Specified from -40°C to +125°C

♦ Small, Thermally Enhanced, 5mm x 5mm TQFN

High-Voltage, Micropower, Single/Dual

Linear Regulators with Supervisory Functions

________________________________________________________________ Maxim Integrated Products

1

Ordering Information

19-3875; Rev 1; 8/06

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.

+Denotes lead-free package.

For tape-and-reel, add a T after the “+.” Tape-and-reel are

offered in 2.5k increments. The first placeholder “_” designates

preset output-voltage option and preset reset threshold level;

see Table 1. The second placeholder “_ ” designates the reset

timeout period; see Table 2. For example, the MAX6791TPSD3+

indicates a 3.3V output voltage with a reset threshold of 87.5%

at nominal voltage and a 50ms reset timeout period. Samples

are generally held in stock. Nonstandard versions require a 2.5k

minimum order quantity.

EVALUATION

KIT

AVAILABLE

PART

TEMP

RANGE

PIN-

PACKAGE

PKG

CODE

MAX6791TP_D _+

-40°C to +125°C

20 TQFN

T2055-4

MAX6792TP_D _+

-40°C to +125°C

20 TQFN

T2055-4

MAX6793TP_ D_+

-40°C to +125°C

20 TQFN

T2055-4

MAX6794TP_ D_+

-40°C to +125°C

20 TQFN

T2055-4

MAX6795TP_ D_+

-40°C to +125°C

20 TQFN

T2055-4

MAX6796TP_D _+

-40°C to +125°C

20 TQFN

T2055-4

Typical Application Circuit, Pin Configurations, and Selector

Guide appear at end of data sheet.