
General Description
The MAX6746–MAX6753 low-power microprocessor
(P) supervisory circuits monitor single/dual system
supply voltages from 1.575V to 5V and provide maxi-
mum adjustability for reset and watchdog functions.
These devices assert a reset signal whenever the VCC
supply voltage or RESET IN falls below its reset thresh-
old or when manual reset is pulled low. The reset output
remains asserted for the reset timeout period after VCC
and RESET IN rise above the reset threshold. The reset
function features immunity to power-supply transients.
The MAX6746–MAX6753 have ±2% factory-trimmed
reset threshold voltages in approximately 100mV incre-
ments from 1.575V to 5.0V and/or adjustable reset
threshold voltages using external resistors.
The reset and watchdog delays are adjustable with
external capacitors. The MAX6746–MAX6751 contain a
watchdog select input that extends the watchdog time-
out period by 128x. The MAX6752/MAX6753 contain a
window watchdog timer that looks for activity outside an
expected window of operation.
The MAX6746–MAX6753 are available with a push-pull
or open-drain active-low RESET output. The MAX6746–
MAX6753 are available in an 8-pin SOT23 package and
are fully specified over the automotive temperature
range (-40°C to +125°C).
Applications
Features
Factory-Set Reset Threshold Options from 1.575V
to 5V in ~100mV Increments
Adjustable Reset Threshold Options
Single/Dual Voltage Monitoring
Capacitor-Adjustable Reset Timeout
Capacitor-Adjustable Watchdog Timeout
Min/Max (Windowed) Watchdog Option
Manual Reset Input Option
Guaranteed RESET Valid for VCC ≥ 1V
3.7A Supply Current
Push-Pull or Open-Drain RESET Output Options
Power-Supply Transient Immunity
Small 8-Pin SOT23 Packages
MAX6746–MAX6753
P Reset Circuits with Capacitor-Adjustable
Reset/Watchdog Timeout Delay
________________________________________________________________ Maxim Integrated Products
1
WDI
WDS
GND
1
2
8
7
VCC
RESET
SWT
SRT
RESET IN (MR)
( ) ARE FOR MAX6746 AND MAX6747 ONLY.
TOP VIEW
3
4
6
5
MAX6746–
MAX6751
SOT23-8
Pin Configurations
19-2530; Rev 3; 12/05
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.
Note: “_ _” represents the two number suffix needed when
ordering the reset threshold voltage value for the
MAX6746/MAX6747 and MAX6750–MAX6753. The reset
threshold voltages are available in approximately 100mV incre-
ments. Table 2 contains the suffix and reset factory-trimmed
voltages. All devices are available in tape-and-reel only. There
is a 2500-piece minimum order increment for standard ver-
sions (see Table 3). Sample stock is typically held on standard
versions only. Nonstandard versions require a minimum order
increment of 10,000 pieces. Contact factory for availability.
Devices are available in both leaded and lead-free packaging.
Specify lead-free by replacing “-T” with “+T” when ordering.
Medical Equipment
Automotive
Intelligent Instruments
Portable Equipment
Battery-Powered
Computers/Controllers
Embedded Controllers
Critical P Monitoring
Set-Top Boxes
Computers
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX6746KA_ _-T
-40°C to +125°C
8 SOT23-8
MAX6747KA_ _-T
-40°C to +125°C
8 SOT23-8
MAX6748KA-T
-40°C to +125°C
8 SOT23-8
MAX6749KA-T
-40°C to +125°C
8 SOT23-8
MAX6750KA_ _-T
-40°C to +125°C
8 SOT23-8
MAX6751KA_ _-T
-40°C to +125°C
8 SOT23-8
MAX6752KA_ _-T
-40°C to +125°C
8 SOT23-8
MAX6753KA_ _-T
-40°C to +125°C
8 SOT23-8
Selector Guide appears at end of data sheet.
Typical Operating Circuit appears at end of data sheet.
Pin Configurations continued at end of data sheet.