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Rainbow Electronics MAX6796 User Manual

General description, Applications, Features

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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

MAX6791–MAX6796

High-Voltage, Micropower, Single/Dual

Linear Regulators with Supervisory Functions

________________________________________________________________ Maxim Integrated Products

1

Ordering Information

19-3875; Rev 0; 11/05

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

M A X6 7 9 1 TP _D _+

-40°C to +125°C

20 TQFN

T2055-4

M A X6 7 9 2 TP _D _+

-40°C to +125°C

20 TQFN

T2055-4

M A X6 7 9 3 TP _ D _+

-40°C to +125°C

20 TQFN

T2055-4

M A X6 7 9 4 TP _ D _+

-40°C to +125°C

20 TQFN

T2055-4

M A X6 7 9 5 TP _ D _+

-40°C to +125°C

20 TQFN

T2055-4

M A X6 7 9 6 TP _D _+

-40°C to +125°C

20 TQFN

T2055-4

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