
2007 Microchip Technology Inc.
DS21615C-page 1
TCM811/TCM812
Features
Precision VDD Monitor for 2.0V, 2.8V, 3.0V, 3.3V,
5.0V Nominal Supplies
Manual Reset Input
140 ms Minimum RESET Output Duration
RESET Output Valid to VDD = 1.0V (TCM811)
Low 6 A (typ.) Supply Current
VDD Transient Immunity
Small 4-Pin SOT-143 Package
No External Components
Replacement for MAX811/812 and Offers a Lower
Threshold Voltage Option
Push-Pull RESET Output
Temperature Range:
- Commercial (C) -40°C to +85°C
Applications
Computers
Embedded Systems
Battery Powered Equipment
Critical Microcontroller Power Supply Monitoring
Typical Application Circuit
General Description
The TCM811 and TCM812 are cost effective system
supervisory circuits designed to monitor V DD in digital
systems and provide a reset signal to the host
controller when necessary. A manual reset input is
provided to override the reset monitor and is suitable
for use as a push-button reset. No external
components are required.
The reset output is driven active within 20 s (5 s for
F version) of VDD falling through the reset voltage
threshold. RESET is maintained active for a minimum
of 140 ms after VDD rises above the reset threshold.
The TCM812 has an active high RESET output while
the TCM811 has an active low RESET output. The
output of the TCM811 is valid down to VDD =1V. Both
devices are available in a 4-Pin SOT-143 package,
specified with a temperature range of -40°C to +85°C.
The TCM811/TCM812 are optimized to reject fast
transient glitches on the VDD line. A low supply current
of 6 A (VDD = 3.3V) makes these devices ideal for
battery powered applications.
Package Types:
TCM811
V
DD
V
DD
V
DD
RESET
INPUT
(Active Low)
GND
MR
PUSH
BUTTON
PIC
Microcontroller
4
3
2
0.1F
V
DD
TCM811 RESET
GND
TC
M8
11
TCM8
12
1
2
TCM812 (RESET)
3
4
MR
or
SOT-143
4-Pin Reset Monitors