LTC2951CTS8-2#TRPBF Linear Technology, LTC2951CTS8-2#TRPBF Datasheet - Page 12

• Manufacturer Part Number: LTC2951CTS8-2#TRPBF
• Description: IC PB ON/OFF CONTROLLER TSOT23-8
• Manufacturer: Linear Technology

Specifications of LTC2951CTS8-2#TRPBF

• Applications: Push Button, On/Off Controller
• Voltage - Supply: 2.7 V ~ 26.4 V
• Current - Supply: 6µA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: TSOT-23-8, TSOT-8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Input: -

LTC2951-1/LTC2951-2
APPLICATIONS INFORMATION
and the external OFFT capacitor (t
of the OFFT timing (t
ing that EN will be switched low after the KILL turn-off
(t
period. Once a system has finished performing its power-
down operations, it can set KILL low (t
diately set EN low, terminating the KILL turn-off timer. The
release of the PB pin is then debounced with an internal
32ms timer.
The system is now in its reset state: where the LTC2951
is in low power mode (6µA). PB is monitored for a high
to low transition.
12
POWER-ON
KILL
TIMING
KILL
,
Figure 2. Aborted Power-On Sequence for LTC2951-1
PB
EN
OFF DELAY
+ t
6
KILL
t
), an interrupt (INT) is set, signify-
DB, ON
,
µP FAILED TO SET
OFF DELAY, ADDITIONAL
KILL HIGH
6
INTERNAL
–t
512ms
TIMER
5
). At the completion
7
) and thus imme-
t
ABORT
POWER
TURNED OFF
) timeout
2951 F02
KILL
Aborted Power-On Sequence
The power-on sequence is aborted when the KILL remains
low after the end of the 512ms blanking time. Figure 2 is
a simplified version of an aborted power-on sequence.
At time t
turning off the DC/DC converter).
µP Turns Off Power During Normal Operation
Once the system has powered on and is operating nor-
mally, the µP can turn off power by setting KILL low, as
shown in Figure 3. At time t
This immediately pulls EN low, thus turning off the DC/
DC converter.
PB
EN
ABORT
Figure 3. µP Turns Off Power (LTC2951-1)
XXX DON’T CARE
, since KILL is still low, EN pulls low (thus
KILL
PB & KILL IGNORED
, KILL is set low by the µP .
KILL LOW
µP SETS
TURNS OFF
t
KILL
DC/DC
295112fb
2951 F03