MAX6457_V5 Datasheet, PDF (1/15 Pages) Maxim Integrated Products – High-Voltage, Low-Current Voltage Monitors in SOT Packages

19-2534; Rev 5; 7/12
High-Voltage, Low-Current Voltage Monitors in
SOT Packages
General Description
The MAX6457–MAX6460 high supply voltage, low-power
voltage monitors operate over a 4V to 28V supply voltage
range. Each device includes a precision bandgap refer-
ence, one or two low-offset voltage comparators, internal
threshold hysteresis, power-good or reset timeout
options, and one or two high-voltage open-drain outputs.
Two external resistors (three for window detection) set the
trip threshold voltages.
The MAX6457 is a single voltage monitor for undervoltage
or overvoltage detection. A logic-based clear input either
latches the output for overvoltage applications or allows
the device to operate in transparent mode. The MAX6458
includes two comparators (one overvoltage and one
undervoltage) for window detection and a single output to
indicate if the monitored input is within an adjustable volt-
age window. The MAX6459 includes dual overvoltage/
undervoltage comparators with two independent com-
parator outputs. Use the MAX6459 as a window com-
parator with separate undervoltage and overvoltage
outputs or as two independent, single voltage monitors.
The MAX6460 includes a single comparator and an inter-
nal reference, and can also accept an external reference.
The inverting and noninverting inputs of the comparator
are externally accessible to support positive or negative
voltage monitors and to configure the device for active-
high or active-low output logic.
The MAX6457/MAX6458 offer fixed timing options as a
voltage detector with a 50µs typical delay or as a reset cir-
cuit with a 90ms minimum reset timeout delay. The moni-
tored input must be above the adjusted trip threshold (or
within the adjusted voltage window for the MAX6458) for
the selected timeout period before the output changes
state. The MAX6459/MAX6460 offer only a fixed 50µs
timeout period. Internal threshold hysteresis options (0.5%,
5%, and 8.3% for the MAX6457/MAX6458/MAX6459, and
0.5% for the MAX6460) reduce output chatter in noise-
sensitive applications. Each device is available in a small
SOT23 package and specified over the extended temper-
ature range of -40°C to +125°C.
Applications
Undervoltage Monitoring/Shutdown
Overvoltage Monitoring/Protection
Window Voltage Detection Circuitry
Multicell Battery-Stack Powered Equipment
Notebooks, eBooks
Automotive
Industrial
Telecom
Networking
Features
o Wide Supply Voltage Range, 4V to 28V
o Internal 2.25V ±2.5% Reference
o Low Current (3.5µA, typ at 12V)
o Open-Drain n-Channel Output (28V Compliant)
o Internal Threshold Hysteresis Options
(0.5%, 5%, 8.3%)
o Two IN-to-OUT Timeout Period Options
(50µs, 150ms)
o Internal Undervoltage Lockout
o Immune to Short Voltage Transients
o Small SOT23 Packages
o Few External Components
o Fully Specified from -40°C to +125°C
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
MAX6457UKD_ _-T -40°C to +125°C 5 SOT23
MAX6458UKD_ _-T -40°C to +125°C 5 SOT23
MAX6459UT_-T
-40°C to +125°C 6 SOT23
MAX6460UT-T
-40°C to +125°C 6 SOT23
Note: The MAX6457/MAX6458/MAX6459 are available with
factory-trimmed internal hysteresis options. The MAX6457 and
MAX6458 offer two fixed timing options. Select the desired hys-
teresis and timing options using Table 1 or the Selector Guide at
the end of the data sheet, and enter the corresponding letters
and numbers in the part number by replacing “_ _” or “_”. These
devices are offered in tape-and-reel only and must be ordered in
2500-piece increments.
Devices are available in both leaded and lead(Pb)-free/RoHS-
compliant packaging. Specify lead(Pb)-free by replacing “-T”
with “+T” when ordering.
Pin Configurations appear at end of data sheet.
Typical Operating Circuit
BATTERY ^{+21V (NOMINAL)}
CHARGER
VCC
IN DC-DC OUT
CONVERTER
SHDN
5-CELL
Li+
BATTERY
STACK
MAX6457
R1
RPULLUP
IN+
OUT
R2
GND
CLEAR
LOAD
For pricing, delivery, and ordering information, please contact Maxim Direct
1
at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.