LTC2950-1/LTC2950-2
Pushbutton On/Off
Controller
Features
n
n
n
n
n
n
n
n
n
n
Description
Adjustable Pushbutton On/Off Timers
Low Supply Current: 6µA
Wide Operating Voltage Range: 2.7V to 26.4V
EN Output (LTC2950-1) Allows DC/DC Converter
Control
EN Output (LTC2950-2) Allows Circuit Breaker
Control
Simple Interface Allows Graceful µP Shut Down
High Input Voltage PB Pin with Internal Pull Up
Resistor
±10kV ESD HBM on PB Input
Accurate 0.6V Threshold on KILL Comparator Input
8-Pin 3mm × 2mm DFN and ThinSOT™ Packages
Applications
n
n
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Portable Instrumentation Meters
Blade Servers
Portable Customer Service PDA
Desktop and Notebook Computers
The LTC®2950 is a micropower, wide input voltage range,
pushbutton ON/OFF controller. The part contains a pushbutton input with independently programmable ON and OFF
debounce times that control the toggling of an open drain
enable output. The part also contains a simple microprocessor interface to allow for proper system housekeeping
prior to power down. Under system fault conditions, an
internal KILL timer ensures proper power down.
The LTC2950 operates over a wide 2.7V to 26.4V input
voltage range to accommodate a wide variety of input
power supplies. Very low quiescent current (6µA typical)
makes the LTC2950 ideally suited for battery powered
applications. Two versions of the part are available to accommodate either positive or negative enable polarities.
The parts are available in either 8-lead 3mm × 2mm DFN
or ThinSOT packages.
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
Turn On Debounce
VIN
2.7V TO 26.4V
VIN
VOUT
DC/DC
BUCK
SHDN**
EN
VIN
LTC2950-1
PB
GND
ONT
2V/DIV
R1
10k
EN
INT
INT
KILL
KILL
PB
µP/µC
OFFT
2950 TA01
CONT*
0.033µF
COFFT*
0.033µF
10ms/DIV
2950 TA01b
*OPTIONAL
**SHDN INTERNALLY PULLED UP BY DC/DC
295012fd
1
LTC2950-1/LTC2950-2
Absolute Maximum Ratings
(Note 1)
Supply Voltage (VIN)................................... –0.3V to 33V
Input Voltages
PB.............................................................. –6V to 33V
ONT....................................................... –0.3V to 2.7V
OFFT...................................................... –0.3V to 2.7V
KILL.......................................................... –0.3V to 7V
Output Voltages
INT.......................................................... –0.3V to 10V
EN/EN..................................................... –0.3V to 10V
Operating Temperature Range
LTC2950C-1.............................................. 0°C to 70°C
LTC2950C-2.............................................. 0°C to 70°C
LTC2950I-1...........................................–40°C to 85°C
LTC2950I-2...........................................–40°C to 85°C
Storage Temperature Range
DFN Package...................................... –65°C to 125°C
TSOT-23.............................................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec).................... 300°C
Pin Configuration
TOP VIEW
GND 1
ONT 2
PB 3
VIN 4
TOP VIEW
8 INT
9
VIN 1
PB 2
ONT 3
GND 4
7 EN/EN
6 OFFT
5 KILL
8 KILL
7 OFFT
6 EN/EN
5 INT
TS8 PACKAGE
8-LEAD PLASTIC TSOT-23
TJMAX = 125°C, θJA = 140°C/W
DDB8 PACKAGE
8-LEAD (3mm × 2mm) PLASTIC DFN
TJMAX = 125°C, θJA = 165°C/W
EXPOSED PAD (PIN 9) PCB GND CONNECTION OPTIONAL
Order Information
Lead Free Finish
TAPE AND REEL (MINI)
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LTC2950CDDB-1#TRMPBF
LTC2950CDDB-1#TRPBF
LBKP
8-Lead Plastic DFN
0°C to 70°C
LTC2950CDDB-2#TRMPBF
LTC2950CDDB-2#TRPBF
LBNG
8-Lead Plastic DFN
0°C to 70°C
LTC2950IDDB-1#TRMPBF
LTC2950IDDB-1#TRPBF
LBKP
8-Lead Plastic DFN
–40°C to 85°C
LTC2950IDDB-2#TRMPBF
LTC2950IDDB-2#TRPBF
LBNG
8-Lead Plastic DFN
–40°C to 85°C
LTC2950CTS8-1#TRMPBF
LTC2950CTS8-1#TRPBF
LTBKN
8-Lead Plastic TSOT-23
0°C to 70°C
LTC2950CTS8-2#TRMPBF
LTC2950CTS8-2#TRPBF
LTBNF
8-Lead Plastic TSOT-23
0°C to 70°C
LTC2950ITS8-1#TRMPBF
LTC2950ITS8-1#TRPBF
LTBKN
8-Lead Plastic TSOT-23
–40°C to 85°C
LTC2950ITS8-2#TRMPBF
LTC2950ITS8-2#TRPBF
LTBNF
8-Lead Plastic TSOT-23
TRM = 500 pieces. *Temperature grades are identified by a label on the shipping container.
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on lead based finish parts.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
–40°C to 85°C
295012fd
2
LTC2950-1/LTC2950-2
Electrical
Characteristics
The
l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VIN = 2.7V to 26.4V, unless otherwise noted. (Note 2)
SYMBOL
PARAMETER
CONDITIONS
VIN
Supply Voltage Range
Steady State Operation
MIN
l
IIN
VIN Supply Current
System Power On, VIN = 2.7V to 24V
l
VUVL
VIN Undervoltage Lockout
VIN Falling
l
VUVL(HYST)
VIN Undervoltage Lockout
Hysteresis
TYP
2.7
MAX
UNITS
26.4
V
6
12
µA
2.2
2.3
2.4
V
50
300
600
mV
Pushbutton, Enable (PB, EN/EN)
VPB(MIN, MAX)
PB Voltage Range
Single-Ended
l
–1
26.4
V
IPB
PB Input Current
2.5V < VPB < 26.4V
VPB = 1V
VPB = 0.6V
l
l
l
–1
–3
–6
–9
±1
–12
–15
µA
µA
µA
VPB(VTH)
PB Input Threshold
PB Falling
l
0.6
0.8
1
V
VPB(VOC)
PB Open Circuit Voltage
IPB = –1µA
1
1.6
2
tEN/EN, Lock Out
EN/EN Lock Out Time (Note 5)
Enable Released → Enable Asserted
l
200
256
325
ms
IEN/EN(LKG)
EN/EN Leakage Current
VEN/ EN = 1V, Sink Current Off
l
±0.1
µA
VEN/EN(VOL)
EN/EN Voltage Output Low
IEN/ EN = 3mA
l
0.11
0.4
V
V
Debounce Timing Pins (ONT, OFFT)
IONT, OFFT(PU)
ONT/OFFT Pull Up Current
VONT, OFFT = 0V
l
–2.4
–3
–3.6
µA
IONT, OFFT(PD)
ONT/OFFT Pull Down Current
VONT, OFFT = 1.3V
l
2.4
3
3.6
µA
tDB, On
Internal Turn On Debounce Time
ONT Pin Float, PB Falling → Enable Asserted
l
26
32
41
ms
tONT
Additional Adjustable Turn On Time CONT = 1500pF
l
9
11.5
13.5
ms
tDB, Off
Internal Turn Off Debounce Time
l
26
32
41
ms
tOFFT
Additional Adjustable Turn Off Time COFFT = 1500pF
l
9
11.5
13.5
ms
±1
µA
0.11
0.4
V
0.57
0.6
0.63
10
30
50
mV
±0.1
µA
OFFT Pin Float, PB Falling → INT Falling
µP Handshake Pins (INT, KILL)
IINT(LKG)
INT Leakage Current
VINT = 3V
l
VINT(VOL)
INT Output Voltage Low
IINT = 3mA
l
VKILL(TH)
KILL Input Threshold Voltage
KILL Falling
l
VKILL(HYST)
KILL Input Threshold Hysteresis
IKILL(LKG)
KILL Leakage Current
tKILL(PW)
KILL Minimum Pulse Width
VKILL = 0.6V
tKILL(PD)
KILL Propagation Delay
KILL Falling → Enable Released
l
tKILL, On Blank
KILL Turn On Blanking (Note 3)
KILL = Low, Enable Asserted → Enable Released
l
400
tKILL, Off Delay
KILL Turn Off Delay (Note 4)
KILL = High, INT Asserted → Enable Released
l
800
l
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: All currents into pins are positive; all voltages are referenced to
GND unless otherwise noted.
Note 3: The KILL turn on blanking timer period is the waiting period
immediately after the enable output is asserted. This blanking time allows
sufficient time for the DC/DC converter and the µP to perform power up
tasks. The KILL and PB inputs are ignored during this period. If KILL remains
low at the end of this time period, the enable output is released, thus turning
off system power. This time delay does not include tDB, ON or tONT.
30
V
µs
30
µs
512
650
ms
1024
1300
ms
Note 4: The KILL turn off delay is the maximum delay from the initiation
of a shutdown sequence (INT falling), to the release of the enable output.
If the KILL input switches low at any time during this period, enable is
released, thus turning off system power. This time is internally fixed at
1024ms. This time delay does not include tDB, OFF or tOFFT.
Note 5: The enable lock out time is designed to allow an application to
properly power down such that the next power up sequence starts from a
consistent powered down configuration. PB is ignored during this lock out
time. This time delay does not include tDB, ON or tONT.
295012fd
3
LTC2950-1/LTC2950-2
Typical Performance Characteristics
Supply Current vs Temperature
10
10
8
VIN = 2.7V
4
2
6
4
2
0
–50
–25
0
25
50
TEMPERATURE (°C)
75
0
100
0
5
10
15
20
25
ONT Pull-Down Current
vs Temperature
50
VIN = 26.4V
–3.0
VIN = 2.7V
–2.8
100
10
OFFT EXTERNAL CAPACITOR (nF)
–25
0
25
50
TEMPERATURE (°C)
75
0
100
5
0
10
15
VIN (V)
20
25
PB Current vs PB Voltage
–250
TA = 25°C
VIN = 3.3V
–200
–3.2
VIN = 26.4V
–3.0
VIN = 2.7V
–2.8
–2.6
–50
30
2950 G06
PB CURRENT (µA)
tDB, OFF + tOFFT (ms)
2950 G07
20
OFFT Pull-Down Current
vs Temperature
OFFT PULL-DOWN CURRENT (µA)
1000
30
10
–3.4
100
30
TA = 25°C
2950 G05
Turn Off Debounce Time (tDB, OFF
+ tOFFT) vs OFFT External Capacitor
1000
25
20
40
–3.2
–2.6
–50
1000
TA = 25°C
VIN = 3.3V
15
VIN (V)
Internal Default Turn Off
Debounce Time (tDB, OFF) vs VIN
2950 G04
1
10
5
2950 G03
tDB, OFF (ms)
100
10
0
2950 G02
ONT PULL-DOWN CURRENT (µA)
tDB, ON + tONT (ms)
1000
10000
0
30
–3.4
TA = 25°C
VIN = 3.3V
100
10
ONT EXTERNAL CAPACITOR (nF)
20
VIN (V)
Turn On Debounce Time (tDB, ON
+ tONT) vs ONT External Capacitor
1
30
10
2950 G01
10000
TA = 25°C
40
tDB, ON (ms)
VIN = 3.3V
6
IVIN (µA)
IVIN (µA)
8
50
TA = 25°C
VIN = 26.4V
10
Internal Default Turn On
Debounce Time (tDB, ON) vs VIN
Supply Current vs Supply Voltage
–150
–100
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
2950 G08
0
–10
–5
0
5
10 15
PB VOLTAGE (V)
20
25
30
2950 G09
295012fd
4
LTC2950-1/LTC2950-2
Typical Performance Characteristics
PB Voltage vs External PB
Resistance to Ground
300
EN/EN VOL vs Current Load
500
VIN = 3.3V
400
200
EN/EN VOLTAGE (mV)
PB VOLTAGE (mV)
250
TA = 100°C
150
TA = 25°C
TA = –45°C
100
300
200
100
50
0
TA = 25°C
VIN = 3.3V
0
0
5
10
15
20
EXTERNAL PB RESISTANCE TO GROUND (kΩ)
0
2
6
8
4
EN/EN CURRENT LOAD (mA)
2950 G10
2950 G11
EN (LTC2950-1) Voltage vs VIN
1.0
EN (LTC2950-2) Voltage vs VIN
4
TA = 25°C
100k PULL-UP FROM EN TO VIN
TA = 25°C
100k PULL-UP FROM EN TO VIN
3
0.6
EN (V)
EN (V)
0.8
0.4
2
1
0.2
0
10
0
1
2
3
4
VIN (V)
0
0
1
2
3
4
VIN (V)
2950 G12
2950 G13
295012fd
5
LTC2950-1/LTC2950-2
Pin Functions
(TSOT-23/DFN)
VIN (Pin 1/Pin 4): Power Supply Input: 2.7V to 26.4V.
PB (Pin 2/Pin 3): Pushbutton Input. Connecting PB to
ground through a momentary switch provides on/off
control via the EN/EN pin. An internal 100k pull-up resistor connects to an internal 1.9V bias voltage. The rugged
PB input can be pulled up to 26.4V externally without
consuming extra current.
ONT (Pin 3/Pin 2): Additional Adjustable Turn On Time
Input. Placing an external capacitor to ground determines
the additional time (beyond the internal default 32ms)
the PB pin must be held low before the enable output
is asserted. Floating this pin results in a default turn on
debounce time of 32ms.
GND (Pin 4/Pin 1): Device Ground.
INT (Pin 5/Pin 8): Open Drain Interrupt Output. After a
pushbutton turn-off event is detected, the LTC2950 interrupts the system (µP) by bringing the INT pin low. Once the
system finishes its power down and housekeeping tasks,
it sets KILL low, which in turn releases the enable output.
If at the end of the power down timer (1024ms) KILL is
still high, the enable output is released immediately. INT
may optionally be tied to KILL to release the enable output
immediately after the turn-off event has been detected
(INT = low).
EN (LTC2950-1, Pin 6/Pin 7): Open Drain Enable Output.
This pin is intended to enable system power. EN is asserted
high after a valid PB turn on event. EN is released low if: a)
KILL is not driven high (by µP) within 512ms of the initial
valid PB power turn-on event, b) KILL is driven low during normal operation, c) a second valid PB event (power
turn-off) is detected. This pin can connect directly to a
DC/DC converter shutdown pin that provides an internal
pull-up. Otherwise a pull-up resistor to an external supply
is required. The operating range for this pin is 0V to 10V.
EN (LTC2950-2, Pin 6/Pin 7): Open Drain Enable Output.
This pin is intended to enable system power. EN is asserted
low after a valid PB turn-on event. EN releases high if: a)
KILL is not driven high (by µP) within 512ms of the initial
valid PB power turn-on event, b) KILL is driven low during normal operation, c) a second valid PB event (power
turn-off) is detected. This pin can connect directly to a
DC/DC converter shutdown pin that provides an internal
pull-up. Otherwise a pull-up resistor to an external supply
is required. The operating range of this pin is 0V to 10V.
OFFT (Pin 7/Pin 6): Additional Adjustable Turn Off Time
Input. A capacitor to ground determines the additional
time (beyond the internal default 32ms) that the PB pin
must be held low before initiating a power down sequence
(INT falling). Floating this pin results in a default turn off
time of 32ms.
KILL (Pin 8/Pin 5): KILL Input. Forcing KILL low releases
the enable output. During system turn on, this pin is blanked
by a 512ms internal timer to allow the system to pull KILL
high. This pin has an accurate 0.6V threshold and can be
used as a voltage monitor input. If unused, connect to a
low voltage output supply (see Figure 6).
Exposed Pad (Pin 9): Exposed Pad may be left open or
connected to device ground.
295012fd
6
LTC2950-1/LTC2950-2
Block Diagram
EN/EN
VIN
2.7V TO 26.4V
REGULATOR
2.4V
2.4V
PB
KILL
OSCILLATOR
100k
LOGIC
10µS
FILTER
DEBOUNCE
0.6V
0.8V
INT
OSCILLATOR
GND
ONT
OFFT
2950 BD
Timing Diagrams
tKILL(PW)
KILL
tKILL(PD)
EN/EN
2950 TD01
295012fd
7
LTC2950-1/LTC2950-2
TIMING DiagramS
PB
PB & KILL IGNORED
tDB, ON
tONT
tKILL, ON BLANK
16 CYCLES
EN
(LTC2950-1)
EN
(LTC2950-2)
2950 TD02
Power On Timing
PB
tDB, OFF
PB IGNORED
tOFFT
OFFT
16 CYCLES
INT
tKILL, OFF DELAY
EN
(LTC2950-1)
EN
(LTC2950-2)
2950 TD03
Power Off Timing, KILL > 0.6V
295012fd
8
LTC2950-1/LTC2950-2
Applications Information
Description
The LTC2950 is a low power (6µA), wide input voltage
range (2.7V to 26.4V), pushbutton on/off controller that
can interface to a µP and a power supply. The turn-on and
turn-off debounce times are extendable using optional
external capacitors. A simple interface (INT output, KILL
input) allows a system to power on and power off in a
controlled manner.
Turn On
When power is first applied to the LTC2950, the part initializes the output pins. Any DC/DC converters connected
to the EN/EN pin will therefore be held off. To assert the
enable output, PB must be held low for a minimum of
32ms (tDB, ON). The LTC2950 provides additional turn on
debounce time via an optional capacitor connected to the
ONT pin (tONT). The following equation describes the additional time that PB must be held low before asserting
the enable output. CONT is the ONT external capacitor:
CONT = 1.56E-4 [µF/ms] • (tONT – 1ms)
Once the enable output is asserted, any DC/DC converters
connected to this pin are turned on. The KILL input from
the µP is ignored during a succeeding 512ms blanking
time (tKILL, ON BLANK). This blanking time represents the
maximum time required to power up the DC/DC converter
and the µP. If KILL is not brought high during this 512ms
time window, the enable output is released. The assumption
is that 512ms is sufficient time for the system to power up.
Turn Off
To initiate a power off sequence, PB must be held low for a
minimum of 32ms (tDB, OFF). Additional turn off debounce
time may be added via an optional capacitor connected
to the OFFT pin (tOFFT). The following equation describes
the additional time that PB must be held low to initiate a
power off sequence. COFFT is the OFFT external capacitor:
COFFT = 1.56E-4 [µF/ms] • (tOFFT – 1ms)
Once PB has been validly pressed, INT is switched low. This
alerts the µP to perform its power down and housekeeping
tasks. The power down time given to the µP is 1024ms.
Note that the KILL input can be pulled low (thereby releasing
the enable output) at any time after tKILL, ON BLANK period.
Simplified Power On/Off Sequence
Figure 1 shows a simplified LTC2950-1 power on and power
off sequence. A high to low transition on PB (t1) initiates
the power on sequence. This diagram does not show any
bounce on PB. In order to assert the enable output, the
PB pin must stay low continuously (PB high resets timers)
for a time controlled by the default 32ms and the external
ONT capacitor (t2–t1). Once EN goes high (t2), an internal
512ms blanking timer is started. This blanking timer is
designed to give sufficient time for the DC/DC converter
to reach its final voltage, and to allow the µP enough time
to perform power on tasks.
The KILL pin must be pulled high within 512ms of the EN
pin going high. Failure to do so results in the EN pin going
low 512ms after it went high. (EN = low, see Figure 2).
Note that the LTC2950 does not sample KILL and PB until
after the 512ms internal timer has expired. The reason PB
is ignored is to ensure that the system is not forced off
while powering on. Once the 512ms timer expires (t4), the
release of the PB pin is then debounced with an internal
32ms timer. The system has now properly powered on
and the LTC2950 monitors PB and KILL (for a turnoff
command) while consuming only 6µA of supply current.
A high to low transition on PB (t5) initiates the power off
sequence. PB must stay low continuously (PB high resets
debounce timer) for a period controlled by the default 32ms
and the external OFFT capacitor (t6–t5). At the completion
of the OFFT timing (t6), an interrupt (INT) is set, signifying
that EN will be switched low in 1024ms. Once a system
has finished performing its power down operations, it
can set KILL low (t7) and thus immediately set EN low),
terminating the internal 1024ms 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 LTC2950
is in low power mode (6µA). PB is monitored for a high
to low transition.
295012fd
9
LTC2950-1/LTC2950-2
Applications Information
t1
t2
PB
t3
t4
t5
t6
PB & KILL IGNORED
tDB, ON
PB IGNORED
tKILL, ON BLANK
tONT
t7
< tKILL,
OFF DELAY
tDB, OFF
ONT
tOFFT
OFFT
INT
–6V) and above VIN
(2µA),
the PB voltage may fall close to the threshold window. To
mitigate the effect of the board leakage, a 10k resistor to
VIN is recommended (see Figure 9).
VIN
Reverse Battery Protection
To protect the LTC2950 from a reverse battery connection,
place a 1k resistor in series with the VIN pin (see Figure 10).
VIN
LTC2950-1/
LTC2950-2
2.4V
R7
10k
PB
100k
EXTERNAL BOARD
LEAKAGE CURRENT
>2µA
GND
PINS OMITTED
FOR CLARITY
IF EXTERNAL PARASITIC BOARD
LEAKAGE >2µA, USE EXTERNAL
PULL-UP RESISTOR
2950 F09
Figure 9. External Pull-Up Resistor on PB Pin
295012fd
14
LTC2950-1/LTC2950-2
Package Description
DDB Package
8-Lead Plastic DFN (3mm × 2mm)
(Reference LTC DWG # 05-08-1702 Rev B)
0.61 ±0.05
(2 SIDES)
3.00 ±0.10
(2 SIDES)
0.70 ±0.05
2.55 ±0.05
1.15 ±0.05
PACKAGE
OUTLINE
0.25 ± 0.05
0.50 BSC
2.20 ±0.05
(2 SIDES)
PIN 1 BAR
TOP MARK
(SEE NOTE 6)
0.200 REF
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
R = 0.115
TYP
5
R = 0.05
TYP
0.40 ± 0.10
8
2.00 ±0.10
(2 SIDES)
0.56 ± 0.05
(2 SIDES)
0.75 ±0.05
0 – 0.05
4
0.25 ± 0.05
1
PIN 1
R = 0.20 OR
0.25 × 45°
CHAMFER
(DDB8) DFN 0905 REV B
0.50 BSC
2.15 ±0.05
(2 SIDES)
BOTTOM VIEW—EXPOSED PAD
NOTE:
1. DRAWING CONFORMS TO VERSION (WECD-1) IN JEDEC PACKAGE OUTLINE M0-229
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE
295012fd
15
LTC2950-1/LTC2950-2
Package Description
TS8 Package
8-Lead Plastic TSOT-23
(Reference LTC DWG # 05-08-1637 Rev A)
0.40
MAX
2.90 BSC
(NOTE 4)
0.65
REF
1.22 REF
1.4 MIN
3.85 MAX 2.62 REF
2.80 BSC
1.50 – 1.75
(NOTE 4)
PIN ONE ID
RECOMMENDED SOLDER PAD LAYOUT
PER IPC CALCULATOR
0.22 – 0.36
8 PLCS (NOTE 3)
0.65 BSC
0.80 – 0.90
0.20 BSC
0.01 – 0.10
1.00 MAX
DATUM ‘A’
0.30 – 0.50 REF
0.09 – 0.20
(NOTE 3)
1.95 BSC
TS8 TSOT-23 0710 REV A
NOTE:
1. DIMENSIONS ARE IN MILLIMETERS
2. DRAWING NOT TO SCALE
3. DIMENSIONS ARE INCLUSIVE OF PLATING
4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR
5. MOLD FLASH SHALL NOT EXCEED 0.254mm
6. JEDEC PACKAGE REFERENCE IS MO-193
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16
LTC2950-1/LTC2950-2
Revision History
(Revision history begins at Rev D)
REV
DATE
DESCRIPTION
PAGE NUMBER
D
02/11
Revised Typical Application.
1
Revised Absolute Maximum Ratings and Pin Configuration.
2
Updated Electrical Characteristics
3
Revised EN and EN pin descriptions in Pin Functions.
6
Updated Block Diagram
7
Revised Figures 5 and 6.
12
Updated Related Parts.
18
295012fd
Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation
that the interconnection of its circuits as described herein will not infringe on existing patent rights.
17
LTC2950-1/LTC2950-2
Typical Application
9V
BATTERY
VIN
+
R5
910k
R8
1k
VOUT
LT1761-1.8
SHDN
1.8V
VIN
C4
0.1µF
R1
10k
EN
LTC2950-1
INT
INT
PB
KILL
KILL
GND ONT
OFFT
CONT*
0.033µF
COFFT*
0.033µF
*OPTIONAL
µP
2950 F10
Figure 10. Reverse Battery Protection
Related Parts
PART NUMBER
DESCRIPTION
COMMENTS
LTC2900
Programmable Quad Supply Monitor
Adjustable RESET, 10-Lead MSOP and 3mm × 3mm DFN Packages
LTC2904/LTC2905 Pin-Programmable Dual Supply Monitors
Adjustable RESET and Tolerance, 8-Lead SOT-23 and 3mm × 2mm DFN Packages
LTC4411
2.6A Low Loss Ideal Diode in ThinSOT
No External MOSFET, Automatic Switching Between DC Sources
LTC4412HV
PowerPath Controller in ThinSOT
Efficient Diode-ORing, Automatic Switching Between DC Sources, 3V to 36V
LTC4055
USB Power Controller and Li-Ion Charger
Automatic Switchover, Charges 1-Cell Li-Ion Batteries
LTC2951
Micropower Pushbutton On/Off Controller
Adjustable Power-Off Timer
LTC2952
Pushbutton PowerPath Controller with
Supervisor
Automatic Low Loss Switchover Between DC Sources
LTC2953
Pushbutton On/Off Controller with Voltage
Monitoring
High Voltage Pushbutton Controller with 200ms Voltage Reset Monitor
LTC2954
Pushbutton On/Off Controller with µP Interrupt
Allow Controlled Software System Shutdown
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18
Linear Technology Corporation
LT 0211 REV D • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
www.linear.com
LINEAR TECHNOLOGY CORPORATION 2008
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