µP Supervisory Circuits
CAT705, CAT706, CAT813
FEATURES
Accurate under voltage system monitoring
R¯¯E¯S¯E¯T¯ guaranteed valid for VCC = 1.0V
6µA supply current
www.DataSheet4U.c2om00ms RESET pulse width
Watchdog timer function 1.6 sec timeout
Brownout detection system reset for use with
3.0, 3.6, and 5.0 volt systems
Pin and function compatible with the
MAX705/706/813L products
Operating Range from -40°C to +85°C
Available in SOIC 8-lead and MSOP 8-lead
packages
APPLICATIONS
Microprocessor and microcontroller based
systems
Intelligent instruments
Control systems
Critical µP monitors
Portable equipment
PIN CONFIGURATION
SOIC 8-Lead
MR 1
8 WDO
VCC 2
GND 3
7 RESET
(RESET for CAT813)
6 WDI
PFI 4
5 PFO
MSOP 8-Lead
RESET
(RESET for CAT813)
WDO
1
2
8 WDI
7 PFO
MR 3
6 PFI
VCC 4
5 GND
DESCRIPTION
The CAT705, CAT706, and CAT813 provide reset and
monitoring functions for the electronic systems. Each
device monitors the system voltage and maintains a
reset output until that voltage reaches the device’s
specified trip value and then maintains the reset
output active condition until the device’s internal timer
allows the system power supply to stabilize.
The CAT705, CAT706, and CAT813 have a watchdog
input which can be used to monitor a system signal
and cause a reset to be issued if the signal fails to
change state prior to a timeout condition.
The CAT705 and CAT706 provide a manual R¯¯E¯S¯E¯T¯
input which initiate reset if pulled low. The CAT705,
CAT706 and CAT813 provide a RESET output which
is low for the CAT705 and CAT706, but high for the
CAT813.
There is a secondary supply monitor included for
power-fail warning (pin PFI).
The CAT706 has a threshold voltage 4.40V. The
CAT705/ CAT813 have a threshold voltage of 4.65V.
For Ordering Information details, see page 13.
PIN FUNCTIONS
Pin Name
¯M¯R¯
VCC
GND
PFI
¯P¯F¯O¯
WDI
R¯¯E¯S¯E¯T¯
RESET
¯W¯¯D¯O¯
Function
Manual Reset input
Power Supply
Ground
Power Fail voltage monitor Input.
Power Fail Output
Watchdog Timer Input
CMOS Push-Pull Active Low Reset
Output (CAT705 & CAT706)
CMOS Push-Pull Active High Reset
Output (CAT813)
Watchdog Timer Output
© Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
1
Doc. No. MD-3030, Rev. A
