Datasheet RT1720 (Richtek)

RT1720 60V Hot Swap Controller with Fault Timer General Description
The RT1720 is an over-voltage and over-current The RT1720 features include, open-drain fault and protection circuit. It monitors a circuit’s input voltage power-good outputs, and a shutdown input. and current with its adjustable over-voltage and The RT1720 is available in the MSOP-10 package. over-current thresholds and drives an external N-MOSFET switch to connect the input to the output
Features
voltage only when it is safe. Its wide input voltage
Wide Input Operation Range : 5V to 80V
range makes it useful for high-voltage applications and
Negative Input Voltage Rating to −60V
in systems that experience large transient voltages and
Adjustable Output Clamp Voltage
currents, such as automotive, telecom, and industrial
Adjustable Over-Current Protection
applications.
Programmable Timer for Fault Protection
During over-voltage events, the RT1720 quickly
Low Shut Down Current
reduces the gate drive of the external MOSFET to
Internal Charge Pump N-MOSFET Drive
regulate the output voltage at the level chosen by its
Fast 80mA MOSFET Shut-off for Overvoltage
external FB resistors. During over-current events, when
Fault Output Indication
the load draws excessive current, the RT1720 reduces
Applications
the gate drive to regulate the output current at the level Automotive/Avionic Surge Protection set by its external current sense resistor. In both cases Hot Swap/Live Insertion the output voltage or current is linearly regulated, High-Side Switch for Battery Powered Systems thermally stressing the MOSFET load switch. However, Intrinsic Safety Applications an externally-adjustable timer limits the duration of MOSFET stress, eventually signaling a fault and then turning off the MOSFET. The RT1720 then periodically restarts operation to test if the fault has cleared. The timer protects the MOSFET while allowing the load circuit to temporarily operate normally through voltage and current surges, such as load dump in automobiles or spinning up disk drives.
Simplified Application Circuit
VIN RSNS Q1 VOUT 5V to 80V VOUT_Max = 60V R3 C VCC SNS OUT SHDN GATE VOUT
RT1720
R2 FB TMR FLT FAULT R1 CTMR PGOOD POWER GND GOOD Copyright © 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS1720-01 November 2015 www.richtek.com 1