LTC1232_15 Datasheet, PDF (1/8 Pages) Linear Technology – Microprocessor Supervisory Circuits

FEATURES
■ _{Guaranteed Reset Assertion at VCC = 1V}
■ _{8-Pin SO Plastic Package}
■ _{2.0mA Maximum Supply Current}
■ _{4.62V/4.37V Precision Voltage Monitor}
■ _{Power OK/Reset Time Delay: 600ms}
■ _{Minimum External Component Count}
■ _{Superior Upgrade for DS1232}
U
APPLICATIO S
■ _{Critical µP Power Monitoring}
■ _{Intelligent Instruments}
■ _{Computers and Controllers}
■ _{Automotive Systems}
LTC1232
Microprocessor
Supervisory Circuits
DESCRIPTIO
The LTC^®1232 provides power supply monitoring,
watchdog timing and external reset for microprocessor
systems. A precise internal voltage reference and
comparator circuit monitor the power supply line. When
an out-of-tolerance condition occurs, the reset outputs
are forced to active states. The RST output is guaranteed
to remain logic low even with V_CC as low as 1V.
The LTC1232 has an internal watchdog timer which forces
the reset outputs to active states when the Strobe input is
not forced low prior to a preset time-out period. The
watchdog timing can be set to operate on time-out periods
of typically 150ms, 600ms or 1.2 seconds.
The LTC1232 performs push-button reset control.
The LTC1232 debounces the push-button input
and guarantees an active reset pulse width of 250ms
minimum.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
5V DC
PB RST V_CC
TD
ST
LTC1232
TOL
RST
GND
RST
5V DC
MPU
(e.g. 6805)
100k
I/O LINE
RESET
LTC1232 • TA01
RST Output Voltage vs
Supply Voltage
5
4
3
2
1
0
0
1
2
3
4
5
SUPPLY VOLTAGE (V)
LTC1232 • TA02
sn1232 1232fas
1