LTC2911
Precision Triple Supply
Monitor with Power-Fail
Comparator
FEATURES DESCRIPTION
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Ultralow Voltage Reset: V = 0.5V Guaranteed
The LTC 2911 is a low power, high accuracy triple supply
CC
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Monitors Three Inputs Simultaneously:
monitor with a power-fail comparator. Reset timeout may
3.3V, 5V, ADJ (LTC2911-1)
be selected with an external capacitor or set to an internally
3.3V, 2.5V, ADJ (LTC2911-2)
generated 200ms.
3.3V, 1.8V, ADJ (LTC2911-3)
The V1 pin monitors a 3.3V supply. The V2 pin monitors a
3.3V, 1.2V, ADJ (LTC2911-4)
5V, 2.5V, 1.8V, 1.2V or adjustable supply. A third adjustable
3.3V, ADJ, ADJ (LTC2911-5)
input has a nominal 0.5V threshold allowing a resistive
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1.5% Threshold Accuracy
divider to configure its threshold. All three comparators
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Power-Fail Monitor
feature a tight 1.5% threshold accuracy over the entire
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RST State Can Be Held for Margining
operating temperature range while a glitch filter ensures
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Low Supply Current: 30A Typical
reliable reset operation.
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Input Glitch Immunity
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A spare comparator can be configured to provide early
Adjustable Reset Timeout Period
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warning of a low voltage condition. It causes the PFO output
Selectable Internal Timeout Saves Components
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to pull low when the voltage of the PFI input falls below 0.5V,
Space Saving 8-Lead TSOT-23 and 3mm 2mm DFN
allowing the power-fail threshold to be configured with
Packages
a resistive divider. A latch feature on the TMR pin allows
the RST output to be latched to prevent system resets,
APPLICATIONS
simplifying margin testing.
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L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Network Servers
Technology Corporation. All other trademarks are the property of their respective owners.
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Desktop and Notebook Computers
Protected by U.S. Patents, including 6949965, 7292076.
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Automotive and Industrial Electronics
TYPICAL APPLICATION
RST Output Voltage With 10k Pull-Up to V1
3.3V
6
V1 = V2
2.5V
DC/DC SYSTEM
CONVERTER LOGIC 5
1.0V
10k
TMR
4
RESET
V1 RST
LOBAT
V2 PFO
3
76.8k
LTC2911-2
ADJ
2
576k 100k
Li-Ion
+
BATTERY
PFI
1
STACK
GND
100k
t = 200ms
RST
0
2911 TA01a
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5
V1 (V)
2911 TA01b
2911f
1
V (V)
RSTLTC2911
ABSOLUTE MAXIMUM RATINGS (Notes 1, 2, 3)
Supply Voltages Operating Temperature Range
V1, V2 ................................................... 0.3V to 6.5V LTC2911C ................................................ 0C to 70C
Input Voltages LTC2911I.............................................. 40C to 85C
ADJ ....................................................... 0.3V to 6.5V LTC2911H .......................................... 40C to 125C
PFI ........................................................... 0.3V to 2V Storage Temperature Range ................... 65C to 150C
TMR ............................................0.3V to (V1 + 0.3V) Lead Temperature (Soldering, 10 sec)
Output Voltages TSOT-23 ............................................................ 300C
RST, PFO .............................................. 0.3V to 6.5V
PIN CONFIGURATION
TOP VIEW
TOP VIEW
V2 1 8 PFI
PFI 1 8 V2
V1 2 7 ADJ
9
ADJ 2 7 V1
GND
PFO 3 6 TMR
TMR 3 6 PFO
RST GND
GND 4 5 RST 4 5
TS8 PACKAGE
8-LEAD PLASTIC TSOT-23
DDB PACKAGE
8-LEAD (3mm 2mm) PLASTIC DFN
T = 150C, = 195C/W
JMAX JA
T = 150C, = 76C/W
JMAX JA
EXPOSED PAD (PIN 9) IS GND, PCB CONNECTION OPTIONAL
ORDER INFORMATION
LTC2911 C DDB 1 #TRM PBF
LEAD FREE DESIGNATOR
PBF = Lead Free Finish Parts
None = Lead Based Finish Parts
TAPE AND REEL
#TR = Tape and Reel
#TRM = 500-Piece Tape and Reel
PRODUCT SELECTION
1, 2, 3, 4, 5
See Product Selection Guide for Details
PACKAGE TYPE
DDB = 8-Lead (3mm 2mm) Plastic DFN
TS8 = 8-Lead Plastic TSOT-23
TEMPERATURE GRADE
C = Commercial Temperature Range (0C to 70C)
I = Industrial Temperature Range (40C to 85C)
H = Automotive Temperature Range (40C to 125C)
PRODUCT PART NUMBER
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on non-standard lead based finish parts.
For more information on lead free part marking, go to: