TC1275/TC1276/TC1277
3-Pin Reset Monitors for 3.3V Systems
Features
General Description
• Precision V Monitor for 3.3V Systems
The TC1275/TC1276/TC1277 are cost-effective
CC
system supervisor circuits designed to monitor V in
• 100msec Minimum RESET, RESET Output
Duration
CC
digital systems and provide a reset signal to the host
processor when necessary. No external components
are required.
• Output Valid to V = 1.2V
CC
• V Transient Immunity
CC
The reset output is driven active within 20µsec of V
CC
• Small 3-Pin SOT-23B Package
• No External Components
falling through the reset voltage threshold. RESET is
maintained active for a minimum of 100msec after V
CC
rises above the reset threshold. The TC1277 has an
active-high RESET output while the TC1275 and
TC1276 have an active-low RESET output. TC1275
and TC1277 each have a complimentary output while
the TC1276 has an open drain output. The output of the
Applications
• Computers
• Embedded Systems
• Battery Powered Equipment
• Critical µP Power Supply Monitoring
TC1275 and TC1276 is valid down to V = 1.2V. The
CC
TC1277 is valid down to V = 1.8V. All three devices
CC
are available in a 3-Pin SOT-23B package.
Device Selection Table
The TC1275/TC1276/TC1277 devices are optimized to
reject fast transient glitches on the V line.
Part
Number
Temp.
Range
CC
Order
Package
Typical Operating Circuit
TC1275-xENB Complimentary 3-Pin SOT-23B -40°C to +85°C
TC1276-xENB Open Drain 3-Pin SOT-23B -40°C to +85°C
V
CC
TC1277-xENB Complimentary 3-Pin SOT-23B -40°C to +85°C
2
V
V
CC
CC
NOTE: “x” denotes a suffix for VCC threshold (see table below).
Processor
1
RESET
Input
Suffix
Reset V Threshold (V)
RESET
CC
5
3.06
2.88
2.55
TC1275
10
20
GND
3
GND
Package Type
3-Pin SOT-23B
RESET
1
*(RESET)
TC1275-xENB
TC1276-xENB
TC1277-xENB
GND
3
V
2
CC
NOTE: 3-Pin SOT-23B is equivalent to JEDEC TO-236
*( ) is for TC1277
2002 Microchip Technology Inc.
DS21383B-page 1