TC1275 Datasheet, PDF (1/12 Pages) Microchip Technology – 3-Pin Reset Monitors for 3.3V Systems

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