LTC2955_15 Datasheet, PDF (1/20 Pages) Linear Technology – Pushbutton On/Off Controller with Automatic Turn-On

FEATURES
n _{Automatic Turn-On Via Voltage Monitor Input}
n _{Wide Input Supply Range: 1.5V to 36V}
n _{Low Supply Current: 1.2μA}
n _{±25kV ESD HBM on PB Input}
n _{±36V Wide Input Voltage for PB Input}
n _{Low Leakage EN Output Allows DC/DC Converter}
Control (LTC2955-1)
n _{High Voltage EN Output Drives External P-Channel}
MOSFET (LTC2955-2)
n _{Simple Interface Allows Graceful μP Shutdown}
n _{Adjustable Turn-Off Timer}
n _{10-Lead 3mm × 2mm DFN and 8-Lead ThinSOT™}
Packages
APPLICATIONS
n _{Desktop and Notebook Computers}
n _{GPS Devices}
n _{Portable Instruments}
n _{Automotive Electronics}
LTC2955
Pushbutton On/Off
Controller with Automatic
Turn-On
DESCRIPTION
The LTC^®2955 is a micropower, pushbutton on/off control-
ler that manages system power by generating a clean enable
output from the supply monitor input and the debounced
pushbutton input. It features an interrupt output that
notifies the system of a pushbutton or low supply event.
When the system is ready, it may use the power kill input
to shut off power. If the pushbutton remains pressed for
more than the configurable turn-off duration, the system
power is forced off.
The supply input covers a wide range from 1.5V to 36V.
The robust pushbutton input handles wide voltage swings
of ±36V and ESD strikes to ±25kV (human body model)
without latchup or damage. A low 1.2μA supply current
maximizes battery run time. Separate versions are avail-
able for positive or negative enable polarities.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
ThinSOT and PowerPath are trademarks of Linear Technology Corporation. All other trademarks
are the property of their respective owners.
TYPICAL APPLICATION
Automatic Turn-On with Power-Fail Indication
V_TRIP = 5.4V
8.4V
2.32M
402k
0.1μF
LT3008-3.3
3.3V
V_IN
V_OUT
SHDN
1M
EN
V_IN
LTC2955DDB-1
SEL
INT
ON
KILL
PB
PGD
TMR GND
R7
1M
μP
POWER-FAIL
2955 TA01a
Pushbutton On/Off with Interrupt
TURN ON PULSE
PB
SHORT PULSE
LONG PULSE
EN
TURNS ON
STAYS ON
TURNS OFF
INT
INTERRUPT
INTERRUPT
2955 TA01b
2955f
1