LTC7860
High Efficiency Switching
Surge Stopper
Fea T Descrip T
n
High Efficiency V Clamp Stops High Voltage
The LTC 7860 high efficiency surge stopper protects loads
OUT
Input Surges
from high voltage transients. High efficiency permits
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SWITCH-ON Mode 100% Duty Cycle for Normal Operation higher currents and smaller solution sizes. During an
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PROTECTIVE PWM Mode for Transients and Faults input overvoltage event, such as a load dump in vehicles,
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the LTC7860 controls the gate of an external MOSFET to
V Pin to SGND Range: 3.5V to 60V
IN
+
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act as a switching DC/DC regulator (PROTECTIVE PWM
External Input Voltage is Extendable to 200V
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mode). This operation regulates the output voltage to a
Adjustable Output Voltage Clamp
n safe level, allowing the loads to operate through the input
Adjustable Output Overcurrent Protection
n over-voltage event. During normal operation (SWITCH-
Power Inductor Improves Input EMI in Normal Operation
ON mode), the LTC7860 turns on the external MOSFET
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Programmable Fault Timer
continuously, passing the input voltage through to the
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Adjustable Soft-Start for Input Inrush Current Limiting
output. An internal comparator limits the voltage across
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4.5% Retry Duty Cycle During Faults
the current sense resistor and regulates the maximum
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Adjustable Switching Frequency: 50kHz to 850kHz
output current to protect against overcurrent faults.
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Optional Reverse Input Voltage Protection
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Available in Thermally Enhanced 12-lead MSOP Package
An adjustable timer limits the time that the LTC7860 can
spend in overvoltage or overcurrent regulation. When the
a T
timer expires, the external MOSFET is turned off until the
LTC7860 restarts after a cool down period. By strictly
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Industrial and Automotive Power
limiting the time in PROTECTIVE PWM Mode when the
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Telecom Power
power loss is high, the components and thermal design
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Vehicle Power Including ISO7637
can be optimized for normal operation and safely oper-
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Military Power Including MIL1275
ate through high voltage input surges and/or overcurrent
L, LT, LTC, LTM, OPTI-LOOP, Linear Technology, Burst Mode and the Linear logo are registered
faults. An additional PMOS can be added for reverse
trademarks and Hot Swap is a trademark of Linear Technology Corporation. All other trademarks
are the property of their respective owners. Protected by U.S. Patents including 5731694.
battery protection.
Typical a T
V V
IN OUT
6.8H
12m
60V MAX
18V MAX
12V NOM 12V NOM
PROTECTIVE PWM: V Clamped
OUT
3.5V MIN
10F 3.5V MIN
to 18V During a V Surge
IN
5A
60V INPUT SURGE
C = 22F
TMR
1M
V
V
IN
FBN
10V/DIV
V
FB
FREQ
10F
0.47F
18V ADJUSTABLE CLAMP
V
OUT
LTC7860
TMR
CAP 10V/DIV
22F
V
TMR
48.7k
RUN 1V/DIV
680pF
0.1F SS
10k
7860 TA01b
ITH
0.1F
100ms/DIV
SGND PGND
7860 TA01a
7860f
1
For more information www.linear.com/LTC7860
VIN
SENSE
GATE
ion pplica
ions pplica
ion uresLTC7860
a T e Maxi Mu M r a T p c F T
(Notes 1, 2)
TOP VIEW
Input Supply Voltage (V ) ......................... 0.3V to 65V
IN
1
TMR 12 GATE
V -V Voltage ...................................... 0.3V to 6V
IN SENSE 2 V
FREQ 11
IN
SGND 3 10 SENSE
13
V -V Voltage ........................................ 0.3V to 10V
IN CAP
SS 4 PGND 9 CAP
RUN Voltage............................................... 0.3V to 65V
V 5 8 RUN
FB
ITH 6 7 V
FBN
V , TMR Voltages ..................................... 0.3V to 6V
FBN
MSE PACKAGE
SS, ITH, FREQ, V Voltages ........................ 0.3V to 5V
FB
12-LEAD PLASTIC MSOP
Operating Junction Temperature Range
T = 150C, = 40C/W, = 10C/W
JMAX JA JC
EXPOSED PAD (PIN 13) IS PGND, MUST BE SOLDERED TO PCB
(Notes 3, 4) ........................................ 55C to 150C
Storage Temperature Range .................. 65C to 150C
Lead Temperature (Soldering, 10 sec)
MSOP Package .................................................300C
o r D i n F Ma T
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC7860EMSE#PBF LTC7860EMSE#TRPBF 7860 12-Lead Plastic MSOP 40C to 125C
LTC7860IMSE#PBF LTC7860IMSE#TRPBF 7860 12-Lead Plastic MSOP 40C to 125C
LTC7860HMSE#PBF LTC7860HMSE#TRPBF 7860 12-Lead Plastic MSOP 40C to 150C
LTC7860MPMSE#PBF LTC7860MPMSE#TRPBF 7860 12-Lead Plastic MSOP 55C to 150C
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 non-standard lead based finish parts.
For more information on lead free part marking, go to: