OMO ElectronicOMO Electronic
Expand menu
Hello, Sign inMy Account
0 Cart

LTC4251-1IS6#TRPBF

P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18P19-P21P22-P24
1
425112fd
LTC4251/LTC4251-1/
LTC4251-2
For more information www.linear.com/4251
TYPICAL APPLICATION
FEATURES DESCRIPTION
Negative Voltage
Hot Swap Controllers in SOT-23
APPLICATIONS
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
Hot Swap and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks
are the property of their respective owners.
n
Hot Board Insertion
n
Electronic Circuit Breaker
n
–48V Distributed Power Systems
n
Negative Power Supply Control
n
Central Office Switching
n
Programmable Current Limiting Circuit
n
High Availability Servers
n
Disk Arrays
n
Allows Safe Board Insertion and Removal from a
Live –48V Backplane
n
Floating Topology Permits Very High Voltage
Operation
n
Programmable Analog Current Limit with Circuit
Breaker Timer
n
Fast Response Time Limits Peak Fault Current
n
Programmable Timer
n
Programmable Undervoltage/Overvoltage Protection
n
Low Profile (1mm) ThinSOT™ Package
The LT C
®
4251/LTC4251-1/LTC4251-2 negative voltage
Hot Swap™ controllers allow a board to be safely inserted
and removed from a live backplane. Output current is con-
trolled by three stages of current limiting: a timed circuit
breaker, active current limiting and a fast feedforward path
that limits peak current under worst-case catastrophic
fault conditions.
Programmable undervoltage and overvoltage detectors
disconnect the load whenever the input supply exceeds
the desired operating range. The supply input is shunt
regulated, allowing safe operation with very high supply
voltages. A multifunction timer delays initial start-up and
controls the circuit breaker’s response time.
The LTC4251 UV/OV thresholds are designed to match the
standard telecom operating range of –43V to –75V. The
LTC4251-1 UV/OV thresholds extend the operating range
to encompass –36V to –72V. The LTC4251-2 implements
a UV threshold of –43V only.
All parts are available in the 6-Pin SOT-23 package.
–48V, 2.5A Hot Swap Controller Start-Up Behavior
GATE
5V/DIV
SENSE
2.5A/DIV
V
OUT
20V/DIV
425112 TA02
1ms/DIV
+
LTC4251
UV/OV
TIMER
GATE
SENSE
V
IN
V
EE
LOAD
–48RTN
–48RTN
(SHORT PIN)
D
IN
†
DDZ13B**
R1
402k
1%
R
C
10Ω
R
S
0.02Ω
R2
32.4k
1%
–48V
C
T
150nF
C1
10nF
C
C
18nF
C
IN
1µF
C
L
100µF
R
IN
*
10k
500mW
V
OUT
Q1
IRF530S
425112 TA01
4
3
2
1
*TWO 0.25W RESISTORS IN SERIES FOR
R
IN
ON THE PCB ARE RECOMMENDED.
**DIODES, INC.
†RECOMMENDED FOR HARSH ENVIRONMENTS
2
425112fd
LTC4251/LTC4251-1/
LTC4251-2
For more information www.linear.com/4251
PIN CONFIGURATIONABSOLUTE MAXIMUM RATINGS
SENSE 1
V
EE
2
V
IN
3
6 GATE
5 UV/OV*
4 TIMER
TOP VIEW
S6 PACKAGE
6-LEAD PLASTIC SOT-23
*UV FOR LTC4251-2
T
JMAX
= 125°C, θ
JA
= 256°C/W
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
Z
V
IN
to V
EE
Zener Voltage I
IN
= 2mA
l
11.5 13 14.5 V
r
Z
V
IN
to V
EE
Zener Dynamic Impedance I
IN
= 2mA to 30mA 5 Ω
I
IN
V
IN
Supply Current UV/OV = 4V, V
IN
= (V
Z
– 0.3V)
l
0.8 2 mA
V
LKO
V
IN
Undervoltage Lockout Coming Out of UVLO (Rising V
IN
)
l
9.2 11.5 V
V
LKH
V
IN
Undervoltage Lockout Hysteresis 1 V
V
CB
Circuit Breaker Current Limit Voltage V
CB
= (V
SENSE
– V
EE
)
l
40 50 60 mV
V
ACL
Analog Current Limit Voltage V
ACL
= (V
SENSE
– V
EE
)
l
80 100 120 mV
V
FCL
Fast Current Limit Voltage V
FCL
= (V
SENSE
– V
EE
)
l
150 200 300 mV
I
GATE
GATE Pin Output Current UV/OV = 4V, V
SENSE
= V
EE
, V
GATE
= 0V (Sourcing)
UV/OV = 4V, V
SENSE
– V
EE
= 0.15V, V
GATE
= 3V (Sinking)
UV/OV = 4V, V
SENSE
– V
EE
= 0.3V, V
GATE
= 1V (Sinking)
l
40 58
17
190
80 µA
mA
mA
V
GATE
External MOSFET Gate Drive V
GATE
– V
EE
, I
IN
= 2mA
l
10 12 V
Z
V
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Notes 2, 3)
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC4251CS6#PBF LTC4251CS6#TRPBF LTUQ 6-Lead Plastic SOT-23 0°C to 70°C
LTC4251IS6#PBF LTC4251IS6#TRPBF LTUR 6-Lead Plastic SOT-23 –40°C to 85°C
LTC4251-1CS6#PBF LTC4251-1CS6#TRPBF LTQU 6-Lead Plastic SOT-23 0°C to 70°C
LTC4251-1IS6#PBF LTC4251-1IS6#TRPBF LTQV 6-Lead Plastic SOT-23 –40°C to 85°C
LTC4251-2CS6#PBF LTC4251-2CS6#TRPBF LTK6 6-Lead Plastic SOT-23 0°C to 70°C
LTC4251-2IS6#PBF LTC4251-2IS6#TRPBF LTAAZ 6-Lead Plastic SOT-23 –40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on non-standard 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/
Current into V
IN
(100µs Pulse) .............................100mA
Minimum V
IN
Voltage ............................................ – 0.3V
Gate, UV/OV, Timer Voltage........................ –0.3V to 16V
Sense Voltage
............................................ –0.6V to 16V
Current Out of Sense Pin (20µs Pulse)
.............. –200mA
Maximum Junction Temperature
.......................... 125°C
Operating Temperature Range
LTC4251C/LTC4251-1C/LTC4251-2C ........ 0°C to 70°C
LTC4251I/LTC4251-1I/LTC4251-2I ........–40°C to 85°C
Storage Temperature Range
.................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
...................300°C
(Note 1), All Voltages are Referred to V
EE
3
425112fd
LTC4251/LTC4251-1/
LTC4251-2
For more information www.linear.com/4251
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.
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
GATEL
Gate Low Threshold (Before Gate Ramp-Up) 0.5 V
V
UVHI
UV Threshold High LTC4251/LTC4251-2
LTC4251-1
l
l
3.075
2.300
3.225
2.420
3.375
2.540
V
V
V
UVLO
UV Threshold Low LTC4251/LTC4251-2
LTC4251-1
l
l
2.775
2.050
2.925
2.160
3.075
2.270
V
V
V
UVHST
UV Hysteresis LTC4251/LTC4251-2
LTC4251-1
0.30
0.26
V
V
V
OVHI
OV Threshold High LTC4251
LTC4251-1
l
l
5.85
5.86
6.15
6.17
6.45
6.48
V
V
V
OVLO
OV Threshold Low LTC4251
LTC4251-1
l
l
5.25
5.61
5.55
5.91
5.85
6.21
V
V
V
OVHST
OV Hysteresis LTC4251
LTC4251-1
0.60
0.26
V
V
I
SENSE
SENSE Input Current UV/OV = 4V, V
SENSE
= 50mV
l
–30 –15 µA
I
INP
UV/OV Input Current UV/OV = 4V
l
±0.1 ±1 µA
V
TMRH
Timer Voltage High Threshold 4 V
V
TMRL
Timer Voltage Low Threshold 1 V
I
TMR
Timer Current Timer On (Initial Cycle, Sourcing), V
TMR
= 2V
Timer Off (Initial Cycle, Sinking), V
TMR
= 2V
Timer On (Circuit Breaker, Sourcing), V
TMR
= 2V
Timer Off (Cooling Cycle, Sinking), V
TMR
= 2V
5.8
28
230
5.8
µA
mA
µA
µA
t
PLLUG
UV Low to GATE Low 0.7 µs
t
PHLOG
OV High to GATE Low LTC4251/LTC4251-1 1 µs
I
IN
vs Temperature
I
IN
vs V
IN
r
Z
vs Temperature
UV/OV = 4V refers to UV = 4V for the LTC4251-2.
Note 2: All currents into device pins are positive; all currents out of device
pins are negative. All voltages are referenced to V
EE
unless otherwise
specified.
Note 3: UV/OV = 4V refers to UV = 4V for the LTC4251-2.
TYPICAL PERFORMANCE CHARACTERISTICS
TEMPERATURE (°C)
–55
I
IN
(µA)
2000
1800
1600
1400
1200
1000
800
600
400
200
0
–15
25
45 125
425112 G01
–35 5
65
85
105
V
IN
= (V
Z
– 0.3V)
V
IN
(V)
0 2 4 6 8 10 12 14 16 18 20 22
I
IN
(mA)
1000
100
10
1
0.1
425112 G02
T
A
= –40°C
T
A
= 125°C
T
A
= 25°C
T
A
= 85°C
TEMPERATURE (°C)
–55
r
Z
(Ω)
10
9
8
7
6
5
4
3
2
–15
25
45 125
425112 G03
–35 5
65
85
105
I
IN
= 2mA
P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18P19-P21P22-P24

LTC4251-1IS6#TRPBF

Mfr. #:
Buy LTC4251-1IS6#TRPBF
Manufacturer:
Analog Devices Inc.
Description:
Hot Swap Voltage Controllers Neg V Hot Swap Cntrs in SOT-23
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet