LTC2900
Programmable Quad Supply
Monitor with Adjustable Reset Timer
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FEATURES
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DESCRIPTIO
Simultaneously Monitors Four Supplies
16 User Selectable Combinations of 5V, 3.3V, 3V,
2.5V, 1.8V, 1.5V and/or ±Adjustable Voltage
Thresholds
Guaranteed Threshold Accuracy: ±1.5% of
Monitored Voltage Over Temperature
Low Supply Current: 43µA Typ
Adjustable Reset Time
Small MSOP and 3mm × 3mm DFN Packages
Manual Reset Pin
Open-Drain RST Output (LTC2900-1)
Push-Pull RST Output (LTC2900-2)
Power Supply Glitch Immunity
Guaranteed RST for VCC ≥ 1V
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APPLICATIO S
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The reset delay time is adjustable using an external
capacitor and the manual reset input may be used with a
momentary switch to issue reset pulses with programmed
duration. Tight voltage threshold accuracy and glitch
immunity ensure reliable reset operation without false
triggering. The RST output is guaranteed to be in the
correct state for VCC down to 1V. The LTC2900-1 features
an open-drain RST output, while the LTC2900-2 has a
push-pull RST output.
The 43µA supply current makes the LTC2900 ideal for
power conscious systems and it may be configured to
monitor less than four inputs. The parts are available in
the 10-lead MSOP and the 10-lead 3mm × 3mm DFN
packages.
Desktop and Notebook Computers
Multivoltage Systems
Telecom Equipment
Portable Battery-Powered Equipment
Network Servers
, LTC and LT are registered trademarks of Linear Technology Corporation.
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The LTC®2900 is a programmable supply monitor for
systems with up to four supply voltages. One of 16 preset
or adjustable voltage monitor combinations can be selected using an external resistor divider connected to the
program pin. The preset voltage thresholds are accurate
to ±1.5% over temperature.
TYPICAL APPLICATIO
Quad Supply Monitor (5V, 3.3V, 2.5V, 1.8V)
5V
3.3V
DC/DC
CONVERTER
SYSTEM
LOGIC
2.5V
1.8V
C1
0.1µF
C2
0.1µF
R1
59k
1%
R2
40.2k
1%
V3
V4
V1
LTC2900-2
V2
VREF
VPG
GND
RST
PBR
CRT
CRT
47nF
PUSH-BUTTON
RESET
2900 TA01
tRST = 216ms
2900f
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