MAX823SEUK-T Datasheet, PDF (1/10 Pages) Maxim Integrated Products – 5-Pin Microprocessor Supervisory Circuits With Watchdog Timer and Manual Reset

19-0487; Rev 5; 12/05
5-Pin Microprocessor Supervisory Circuits With
Watchdog Timer and Manual Reset
________________General Description
The MAX823/MAX824/MAX825* microprocessor (µP)
supervisory circuits combine reset output, watchdog,
and manual reset input functions in 5-pin SOT23 and
SC70 packages. They significantly improve system relia-
bility and accuracy compared to separate ICs or discrete
components. The MAX823/MAX824/MAX825 are specifi-
cally designed to ignore fast transients on V_CC.
Seven preprogrammed reset threshold voltages are
available (see Reset Threshold Table). All three devices
have an active-low reset output, which is guaranteed to
be in the correct state for V_CC down to 1V. The MAX823
also offers a watchdog input and manual reset input.
The MAX824 offers a watchdog input and a comple-
mentary active-high reset. The MAX825 offers a manual
reset input and a complementary active-high reset. The
Selector Guide explains the functions offered in this
series of parts.
*Pg
________________________Applications
Computers and Controllers
Embedded Controllers
Intelligent Instruments
Automotive Systems
Critical µP Monitoring
Portable/Battery-Powered Equipment
Reset Threshold Table
SUFFIX
L
M
T
S
R
Z (SC70 only)
Y (SC70 only)
RESET
THRESHOLD (V)
4.63
4.38
3.08
2.93
2.63
2.32
2.19
Features
♦ Precision Monitoring of +2.5V, +3V, +3.3V, and
+5V Power Supplies
♦ Operating Current: 6µA (MAX823L/M) (SC70)
2µA (MAX825T/S/R/Z/Y) (SC70)
♦ Fully Specified Over Temperature
♦ 140ms min Power-On Reset
♦ Guaranteed RESET Valid to V_CC = 1V
♦ Power-Supply Transient Immunity
♦ Watchdog Timer with 1.6s Timeout
(MAX823/MAX824)
♦ Manual Reset Input (MAX823/MAX825)
♦ No External Components
Ordering Information
PART^†
TEMP. RANGE PIN-PACKAGE
MAX823_EXK-T -40°C to +85°C
5 SC70-5
MAX823_EUK-T _{-40°C to +125°C} 5 SOT23-5
MAX824_EXK-T -40°C to +85°C
5 SC70-5
†Insert the desired suffix letter (from the Reset Threshold table) into
the blank to complete the part number. All devices are available in
tape-and-reel only. There is a 2500 piece minimum order increment.
Devices are available in both leaded and lead-free packaging.
Specify lead-free by replacing “-T” with “+T” when ordering.
Ordering Information continued at end of data sheet.
______________________Selector Guide
FUNCTION
MAX823 MAX824 MAX825
Active-Low Reset
✔
✔
✔
Active-High Reset
—
✔
✔
Watchdog Input
✔
✔
—
Manual Reset Input
✔
—
✔
Typical Operating Circuit appears at end of data sheet.
Marking Information appears at end of data sheet.
Pin Configurations
TOP VIEW
RESET 1
5 V_CC
RESET 1
5 V_CC
RESET 1
5 V_CC
MAX823
GND 2
MAX824
GND 2
MAX825
GND 2
MR 3
4 WDI
RESET 3
4 WDI
RESET 3
4 MR
SOT23/SC70
SOT23/SC70
SOT23/SC70
________________________________________________________________ Maxim Integrated Products 1
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