E
CAT811, CAT812
4-Pin Microprocessor Power Supply Supervisors
TM
FEATURES
ꢀ Precision monitoring of
+5.0 V (+/- 5%, +/- 10%, +/- 20%),
+3.3 V (+/- 5%, +/ 10%),
ꢀ Direct replacements for the MAX811 and
MAX812 in applications operating over the
industrial temperature range
+3.0 V (+/- 10%) and
+2.5 V (+/- 5%) power supplies
ꢀ Reset valid down to VCC = 1.0 V
ꢀ 6 µA power supply current
ꢀ Offered in two output configurations:
- CAT811: Active LOW reset
ꢀ Power supply transient immunity
ꢀ Compact 4-pin SOT143 package
ꢀ Industrial temperature range: -40˚C to +85˚C
- CAT812: Active HIGH reset
ꢀ Manual reset input
APPLICATIONS
ꢀ Computers
ꢀ Embedded control systems
ꢀ White goods
ꢀ Servers
ꢀ Laptops
ꢀ Power meters
ꢀ Cable modems
ꢀꢀ Wireless communications
ꢀ Intelligent instruments
ꢀ PDAs and handheld equipment
DESCRIPTION
The CAT811 and CAT812 are µP supervisory circuits
that monitor power supplies in digital systems. The
CAT811 and CAT812 are direct replacements for the
MAX811andMAX812inapplicationsoperatingoverthe
industrial temperature range; both have a manual reset
input.
offered to support +5.0 V, +3.3 V, +3.0 V and +2.5 V
systems.
The CAT811 features a RESET push-pull output (active
LOW) and the CAT812 features a RESET push-pull
output (active HIGH).
Fast transients on the power supply are ignored and the
output is guaranteed to be in the correct state at Vcc
levels as low as 1.0 V.
Thesedevicesgeneratearesetsignal,whichisasserted
whilethepowersupplyvoltageisbelowapresetthreshold
level and for at least 140 ms after the power supply level
has risen above that level. The underlying floating gate
technology, AE2(TM) used by Catalyst Semiconductor,
makes it possible to offer any custom reset threshold
value. Seven industry standard threshold levels are
The CAT811/812 are fully specified over the industrial
temperature range (-40˚C to 85˚C) and are available in
a compact 4-pin SOT143 package.
PIN CONFIGURATION
THRESHOLD SUFFIX SELECTOR
Nominal Threshold Threshold Suffix
Voltage
4.63V
4.38V
4.00V
3.08V
2.93V
2.63V
2.32V
Designation
GND
1
2
4
3
V
CC
L
M
J
CAT811
(CAT812)
T
S
R
Z
RESET
(RESET)
© 2004 by Catalyst Semiconductor, Inc., Patent Pending
Characteristics subject to change without notice
Doc. No. 3005, Rev. P
1