MAX6340/
MAX6421–MAX6426
Low-Power, SC70/SOT µP Reset Circuits with
Capacitor-Adjustable Reset Timeout Delay
General Description
Features
The MAX6340/MAX6421–MAX6426 low-power micro-
processor supervisor circuits monitor system voltages
from 1.6V to 5V. These devices perform a single function:
o Monitor System Voltages from 1.6V to 5V
o Capacitor-Adjustable Reset Timeout Period
o Low Quiescent Current (1.6µA typ)
they assert a reset signal whenever the V
supply volt-
CC
age falls below its reset threshold. The reset output
remains asserted for the reset timeout period after V
rises above the reset threshold. The reset timeout is exter-
nally set by a capacitor to provide more flexibility.
o Three RESET Output Options
Push-Pull RESET
CC
Push-Pull RESET
Open-Drain RESET
The MAX6421/MAX6424 have an active-low, push-
pull reset output. The MAX6422 has an active-high,
push-pull reset output and the MAX6340/MAX6423/
MAX6425/MAX6426 have an active-low, open-drain
reset output. The MAX6421/MAX6422/MAX6423 are
offered in 4-pin SC70 or SOT143 packages. The
MAX6340/MAX6424/MAX6425/MAX6426 are available
in 5-pin SOT23-5 packages.
o Guaranteed Reset Valid to V
= 1V
CC
o Immune to Short V
Transients
CC
o Small 4-Pin SC70, 4-Pin SOT143, and 5-Pin SOT23
Packages
o MAX6340 Pin Compatible with LP3470
o MAX6424/MAX6425 Pin Compatible with
NCP300–NCP303, MC33464/MC33465,
S807/S808/S809, and RN5VD
o MAX6426 Pin Compatible with PST92XX
Applications
Ordering Information
Portable Equipment
Battery-Powered Computers/Controllers
Automotive
PART
TEMP RANGE
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
PIN-PACKAGE
5 SOT23-5
5 SOT23-5
4 SC70-4
MAX6340UK_ _-T
MAX6340UK_ _/V+T
MAX6421XS_ _-T
MAX6421US_ _-T
MAX6422XS_ _-T
MAX6422US_ _-T
MAX6423XS_ _-T
MAX6423US_ _-T
MAX6424UK_ _-T
MAX6425UK_ _-T
MAX6426UK_ _-T
Medical Equipment
Intelligent Instruments
Embedded Controllers
Critical µP Monitoring
Set-Top Boxes
4 SOT143-4
4 SC70-4
4 SOT143-4
4 SC70-4
4 SOT143-4
5 SOT23-5
5 SOT23-5
5 SOT23-5
Computers
Typical Operating Circuit appears at end of data sheet.
Note: The MAX6340/MAX6421–MAX6426 are available with
factory-trimmed reset thresholds from 1.575V to 5.0V in approxi-
mately 0.1V increments. Insert the desired nominal reset thresh-
old suffix (from Table 1) into the blanks. There are 50 standard
versions with a required order increment of 2500 pieces. Sample
stock is generally held on standard versions only (see Standard
Versions Table). Required order increment is 10,000 pieces for
nonstandard versions. Contact factory for availability. All devices
are available in tape-and-reel only.
Pin Configurations
TOP VIEW
+
V
CC
1
2
4
3
RESET
(RESET)
MAX6421X
MAX6422X
MAX6423X
SRT
GND
Devices are available in both leaded and lead-free packaging.
Specify lead-free by replacing "-T" with "+T" when ordering.
SC70
/V denotes an automotive qualified part.
( ) ARE FOR THE MAX6422
Typical Operating Circuit appears at end of data sheet.
Selector Guide appears at end of data sheet.
Pin Configurations continued at end of data sheet.
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
19-2440; Rev 5; 12/13