LTC2956
Wake-Up Timer with
Pushbutton Control
FEATURES DESCRIPTION
n
1.5V to 36V Supply Input Range The LTC 2956 is a micropower, wide input voltage range,
n
Adjustable Wake-Up Period: 250ms to 39 Days configurable wake-up timer with pushbutton control. It
n
Adjustable Maximum Awake Time periodically wakes up and turns on a connected system
n
0.8A Quiescent Current to perform tasks like monitoring temperature or capturing
n
0.3A Shutdown Current images. After completing the task, the LTC2956 turns the
n
Pushbutton Input with Debouncing system off to conserve power.
n
Low Leakage EN Output Allows DC/DC Converter
The wake-up timer period can be adjusted from 250ms to
Control (LTC2956-1)
39 days using configuration resistors. The system awake
n
High Voltage EN Output Drives External P-Channel
time can be controlled by the input pulse at the SLEEP
MOSFET (LTC2956-2)
pin or adjusted by the capacitor at the ONMAX pin. The
n
25kV ESD HBM on PB Input
LTC2956 operates over a wide supply input range from
n
12-Lead 3mm 3mm QFN and MSOP Packages
1.5V to 36V. The low 800nA quiescent current suits bat-
tery powered applications.
APPLICATIONS
The pushbutton input allows the user to shutdown, turn
n on or reset the wake-up timer. With the timer in shutdown,
Heartbeat Timers
n the quiescent current drops to 300nA. The LTC2956 also
Periodic Wake-Up Control
n provides three status outputs to indicate mode transitions
Portable and Battery-Powered Equipment
n and pushbutton events. Two versions are available for
Intervalometers
n applications requiring either positive or negative enable
Data Acquisition
polarities.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
PowerPath and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks
are the property of their respective owners.
TYPICAL APPLICATION
LT3060
V
BAT
V V V
+ IN OUT MAIN
SHORT PRESS STARTS LONG PRESS STOPS
SHDN
1F CYCLING TIMER CYCLING TIMER
10k 10k
PB
V EN
IN 10k
P SHUTS OFF
PBOUT
ONMAX LTC2956-1
POWER
TURNED ON SLEEP
1.5nF
ONALERT
TURNING OFF
OFFALERT
P
PB TIMER PERIODICALLY
SLEEP
ENABLES POWER
GND
LONG RANGE PERIOD
EN
100k
100k
t t
AWAKE SLEEP
280k 9.76k
2956 TA01b
t
PERIOD
t = 1s, t = 20ms, t = 250ms
LONG ONMAX PERIOD 2956 TA01a
2956fa
1
For more information www.linear.com/LTC2956LTC2956
ABSOLUTE MAXIMUM RATINGS
(Note 1)
V (Note 3) ................................................ 0.3V to 40V Operating Temperature Range:
IN
Input Voltages: LTC2956C ................................................ 0C to 70C
PB ........................................................... 40V to 40V LTC2956I .............................................40C to 85C
SLEEP ...................................................... 0.3V to 6V Storage Temperature Range:
LONG, PERIOD, RANGE, ONMAX ............0.3V to 3.6V QFN Package ..................................... 65C to 150C
Output Voltages: MSOP Package .................................. 65C to 150C
ONALERT, PBOUT, OFFALERT ................... 0.3V to 6V Lead Temperature (Soldering, 10 sec):
EN/EN .................................................... 0.3V to 40V MSOP Package .................................................300C
PIN CONFIGURATION
TOP VIEW
TOP VIEW
12 11 10
ONMAX 1 12 ONALERT
ONALERT 1 9 *EN/EN LONG 2 11 SLEEP
13
RANGE 3 10 OFFALERT
ONMAX 2 8 PB
GND
PERIOD 4 9 PBOUT
LONG 3 7 GND
5
V 8 *EN/EN
IN
6
GND 7 PB
4 5 6
MS PACKAGE
12-LEAD PLASTIC MSOP
T = 125C, = 135C/W
JMAX JA
*PIN 8 IS EN FOR LTC2956-1 AND IS EN FOR LTC2956-2
UD PACKAGE
12-LEAD (3mm 3mm) PLASTIC QFN
T = 125C, = ~68C/W
JMAX JA
EXPOSED PAD (PIN 13) IS GND, PCB CONNECTION OPTIONAL
*PIN 9 IS EN FOR LTC2956-1 AND IS EN FOR LTC2956-2
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC2956CUD-1#PBF LTC2956CUD-1#TRPBF LGNH 12-Lead (3mm 3mm) Plastic QFN 0C to 70C
LTC2956CUD-2#PBF LTC2956CUD-2#TRPBF LGTC 12-Lead (3mm 3mm) Plastic QFN 0C to 70C
LTC2956IUD-1#PBF LTC2956IUD-1#TRPBF LGNH 12-Lead (3mm 3mm) Plastic QFN 40C to 85C
LTC2956IUD-2#PBF LTC2956IUD-2#TRPBF LGTC 12-Lead (3mm 3mm) Plastic QFN 40C to 85C
LTC2956CMS-1#PBF LTC2956CMS-1#TRPBF 29561 12-Lead Plastic MSOP 0C to 70C
LTC2956CMS-2#PBF LTC2956CMS-2#TRPBF 29562 12-Lead Plastic MSOP 0C to 70C
LTC2956IMS-1#PBF LTC2956IMS-1#TRPBF 29561 12-Lead Plastic MSOP 40C to 85C
LTC2956IMS-2#PBF LTC2956IMS-2#TRPBF 29562 12-Lead Plastic MSOP 40C to 85C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
Consult LTC Marketing for information on nonstandard lead based finish parts.
For more information on lead free part marking, go to: