LTC2911_15 Datasheet, PDF (1/20 Pages) Linear Technology – Precision Triple Supply Monitor with Power-Fail Comparator

FEATURES
n _{Ultralow Voltage Reset: VCC = 0.5V Guaranteed}
n _{Monitors Three Inputs Simultaneously:}
3.3V, 5V, ADJ (LTC2911-1)
3.3V, 2.5V, ADJ (LTC2911-2)
3.3V, 1.8V, ADJ (LTC2911-3)
3.3V, 1.2V, ADJ (LTC2911-4)
3.3V, ADJ, ADJ (LTC2911-5)
n _{±1.5% Threshold Accuracy}
n _{Power-Fail Monitor}
n _{RST State Can Be Held for Margining}
n _{Low Supply Current: 30µA Typical}
n _{Input Glitch Immunity}
n _{Adjustable Reset Timeout Period}
n _{Selectable Internal Timeout Saves Components}
n _{Space Saving 8-Lead TSOT-23 and 3mm × 2mm DFN}
Packages
APPLICATIONS
n _{Network Servers}
n _{Desktop and Notebook Computers}
n _{Automotive and Industrial Electronics}
LTC2911
Precision Triple Supply
Monitor with Power-Fail
Comparator
DESCRIPTION
The LTC^®2911 is a low power, high accuracy triple supply
monitor with a power-fail comparator. Reset timeout may
be selected with an external capacitor or set to an internally
generated 200ms.
The V1 pin monitors a 3.3V supply. The V2 pin monitors a
5V, 2.5V, 1.8V, 1.2V or adjustable supply. A third adjustable
input has a nominal 0.5V threshold allowing a resistive
divider to configure its threshold. All three comparators
feature a tight 1.5% threshold accuracy over the entire
operating temperature range while a glitch filter ensures
reliable reset operation.
A spare comparator can be configured to provide early
warning of a low voltage condition. It causes the PFO output
to pull low when the voltage of the PFI input falls below 0.5V,
allowing the power-fail threshold to be configured with
a resistive divider. A latch feature on the TMR pin allows
the RST output to be latched to prevent system resets,
simplifying margin testing.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Protected by U.S. Patents, including 6949965, 7292076.
TYPICAL APPLICATION
3.3V
DC/DC ^2.5V
CONVERTER _1.0V
SYSTEM
LOGIC
+ ^Li-Ion
576k
BATTERY
STACK _100k
76.8k
100k
TMR
10k
RESET
V1
RST
V2
PFO ^LOBAT
LTC2911-2
ADJ
PFI
GND
t_RST = 200ms
2911 TA01a
RST Output Voltage With 10k Pull-Up to V1
6
V1 = V2
5
4
3
2
1
0
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5
V1 (V)
2911 TA01b
2911f
1