TCM809/TCM810
3-Pin Microcontroller Reset Monitors
Features
• Precision V
DD
Monitor for 2.5V, 3.0V, 3.3V, 5.0V
Nominal System Voltage Supplies
• 140 msec Minimum RESET Time Out Period
• RESET Output to V
DD
= 1.0V (TCM809)
• Low Supply Current, 9 µA (typ.)
• V
DD
Transient Immunity
• Small 3-Pin SC-70 and SOT-23B Packages
• No External Components
• Push-Pull RESET Output
• Temperature Range:
- Industrial, SC-70 (E): -40°C to +85°C
- Extended, SOT-23, SC-70 (V): -40°C to +125°C
General Description
The TCM809 and TCM810 are cost-effective system
supervisor circuits designed to monitor V
DD
in digital
systems and provide a reset signal to the host proces-
sor, when necessary. No external components are
required.
The RESET output is typically driven active within
65 µsec of V
DD
falling through the reset voltage thresh-
old. RESET is maintained active for a minimum of
140 msec after V
DD
rises above the reset threshold.
The TCM810 has an active-high RESET output, while
the TCM809 has an active-low RESET output. The out-
put of the TCM809/TCM810 is valid down to V
DD
= 1V.
Both devices are available in 3-Pin SC-70 and SOT-23B
packages.
The TCM809/TCM810 is optimized to reject fast
transient glitches on the V
DD
line. A low supply current
of 9 µA (typ., V
DD
= 3.3V) make these devices suitable
for battery-powered applications.
Applications
•
•
•
•
•
Computers
Embedded Systems
Battery-Powered Equipment
Critical Microcontroller Power Supply Monitoring
Automotive
Pin Configurations
SOT-23B/SC-70
Typical Application Circuit
V
DD
3
V
DD
V
DD
PICmicro
®
Microcontroller
2
RESET
INPUT
(Active-Low)
GND
TCM809
RESET
TCM810
(RESET)
2
GND 1
TCM809/
TCM810
3
V
DD
TCM809
RESET
GND
1
Note:
3-Pin SOT-23B is equivalent to
JEDEC TO-236.
2004 Microchip Technology Inc.
DS21661C-page 1