Datasheet LTC7860 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | High Efficiency Switching Surge Stopper |
| Pages / Page | 26 / 1 — FeaTures. DescripTion. High Efficiency VOUT Clamp Stops High Voltage. … |
| File Format / Size | PDF / 843 Kb |
| Document Language | English |
FeaTures. DescripTion. High Efficiency VOUT Clamp Stops High Voltage. Input Surges
Model Line for this Datasheet
Text Version of Document
LTC7860 High Efficiency Switching Surge Stopper
FeaTures DescripTion
n
High Efficiency VOUT Clamp Stops High Voltage
The LTC®7860 high efficiency surge stopper protects loads
Input Surges
from high voltage transients. High efficiency permits n
SWITCH-ON Mode 100% Duty Cycle for Normal Operation
higher currents and smaller solution sizes. During an n
PROTECTIVE PWM Mode for Transients and Faults
input overvoltage event, such as a load dump in vehicles, n
VIN Pin to SGND Range: 3.5V to 60V
the LTC7860 controls the gate of an external MOSFET to n
External Input Voltage is Extendable to 200V+
act as a switching DC/DC regulator (PROTECTIVE PWM n
Adjustable Output Voltage Clamp
mode). This operation regulates the output voltage to a n
Adjustable Output Overcurrent Protection
safe level, allowing the loads to operate through the input n Power Inductor Improves Input EMI in Normal Operation over-voltage event. During normal operation (SWITCH- n Programmable Fault Timer ON mode), the LTC7860 turns on the external MOSFET n Adjustable Soft-Start for Input Inrush Current Limiting continuously, passing the input voltage through to the n output. An internal comparator limits the voltage across 4.5% Retry Duty Cycle During Faults n the current sense resistor and regulates the maximum Adjustable Switching Frequency: 50kHz to 850kHz n output current to protect against overcurrent faults. Optional Reverse Input Voltage Protection n 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
applicaTions
timer expires, the external MOSFET is turned off until the LTC7860 restarts after a cool down period. By strictly n Industrial and Automotive Power limiting the time in PROTECTIVE PWM Mode when the n Telecom Power power loss is high, the components and thermal design n Vehicle Power Including ISO7637 can be optimized for normal operation and safely oper- n 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 trademarks and Hot Swap is a trademark of Linear Technology Corporation. All other trademarks faults. An additional PMOS can be added for reverse are the property of their respective owners. Protected by U.S. Patents including 5731694. battery protection.
Typical applicaTion
VIN V 12mΩ 6.8µH OUT 60V MAX 18V MAX 12V NOM 12V NOM
PROTECTIVE PWM: VOUT Clamped
3.5V MIN 10µF 3.5V MIN
to 18V During a V
5A
IN Surge
60V INPUT SURGE CTMR = 22µF VIN TE 1M GA VFBN SENSE VIN 10V/DIV VFB FREQ 0.47µF 10µF 18V ADJUSTABLE CLAMP VOUT CAP LTC7860 TMR 10V/DIV 22µF VTMR RUN 48.7k 1V/DIV 680pF 0.1µF 10k SS ITH 0.1µF 7860 TA01b SGND PGND 100ms/DIV 7860 TA01a 7860f For more information www.linear.com/LTC7860 1
FeaTures DescripTion
n
High Efficiency VOUT Clamp Stops High Voltage
The LTC®7860 high efficiency surge stopper protects loads
Input Surges
from high voltage transients. High efficiency permits n
SWITCH-ON Mode 100% Duty Cycle for Normal Operation
higher currents and smaller solution sizes. During an n
PROTECTIVE PWM Mode for Transients and Faults
input overvoltage event, such as a load dump in vehicles, n
VIN Pin to SGND Range: 3.5V to 60V
the LTC7860 controls the gate of an external MOSFET to n
External Input Voltage is Extendable to 200V+
act as a switching DC/DC regulator (PROTECTIVE PWM n
Adjustable Output Voltage Clamp
mode). This operation regulates the output voltage to a n
Adjustable Output Overcurrent Protection
safe level, allowing the loads to operate through the input n Power Inductor Improves Input EMI in Normal Operation over-voltage event. During normal operation (SWITCH- n Programmable Fault Timer ON mode), the LTC7860 turns on the external MOSFET n Adjustable Soft-Start for Input Inrush Current Limiting continuously, passing the input voltage through to the n output. An internal comparator limits the voltage across 4.5% Retry Duty Cycle During Faults n the current sense resistor and regulates the maximum Adjustable Switching Frequency: 50kHz to 850kHz n output current to protect against overcurrent faults. Optional Reverse Input Voltage Protection n 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
applicaTions
timer expires, the external MOSFET is turned off until the LTC7860 restarts after a cool down period. By strictly n Industrial and Automotive Power limiting the time in PROTECTIVE PWM Mode when the n Telecom Power power loss is high, the components and thermal design n Vehicle Power Including ISO7637 can be optimized for normal operation and safely oper- n 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 trademarks and Hot Swap is a trademark of Linear Technology Corporation. All other trademarks faults. An additional PMOS can be added for reverse are the property of their respective owners. Protected by U.S. Patents including 5731694. battery protection.
Typical applicaTion
VIN V 12mΩ 6.8µH OUT 60V MAX 18V MAX 12V NOM 12V NOM
PROTECTIVE PWM: VOUT Clamped
3.5V MIN 10µF 3.5V MIN
to 18V During a V
5A
IN Surge
60V INPUT SURGE CTMR = 22µF VIN TE 1M GA VFBN SENSE VIN 10V/DIV VFB FREQ 0.47µF 10µF 18V ADJUSTABLE CLAMP VOUT CAP LTC7860 TMR 10V/DIV 22µF VTMR RUN 48.7k 1V/DIV 680pF 0.1µF 10k SS ITH 0.1µF 7860 TA01b SGND PGND 100ms/DIV 7860 TA01a 7860f For more information www.linear.com/LTC7860 1
