(

)

6

dVdT

EXT

T

10

VIN

C

70pF

=

´

´

+

OUT

dV

Desired output slew rate

dT

=

(

)

OUT

dVdT

EXT

INT

dVdT

dV

dT

I

C

C

GAIN

æ

ö

ç

÷

è

ø

=

+

´

TPS2592Ax

TPS2592Bx

www.ti.com

SLVSC11A – JUNE 2013 – REVISED JUNE 2013

DEVICE OPERATION

The

TPS2592xx

is

a

hot-swap

controller

with

integrated

power

switch

that

is

used

to

manage

current/voltage/start-up voltage ramp to a connected load. The device starts its operation by monitoring the VIN

on this pin will enable the internal MOSFET and also start charging the gate of external blocking FET (if

connected) via the BFET pin. As VIN rises, the internal MOSFET of the device and external FET (if connected)

the internal MOSFET is turned off and BFET pin is discharged, thereby blocking the flow of current from VIN to

OUT. User also has the ability to modify the output voltage ramp time by connecting a capacitor between dV/dT

pin and GND.

Having successfully completed its start-up sequence, the device now actively monitors its load current and input

typically 160°C, the thermal shutdown circuitry will shut down the internal MOSFET thereby disconnecting the

load from the supply. In the TPS2592xL, the output will remain disconnected (MOSFET open) until power to

device is recycled or EN/UVLO is toggled (pulled low and then high). The TPS2592xA device will remain off

This ON and OFF cycle will continue until fault is cleared.

DETAILED PIN DESCRIPTION

GND: This is the most negative voltage in the circuit and is used as a reference for all voltage measurements

unless otherwise specified.

VIN: Input voltage to the TPS2592xx. A ceramic bypass capacitor close to the device from VIN to GND is

recommended to alleviate bus transients. The recommended operating voltage range is 4.5V – 13.8V for

TPS2592Ax and 4.5V – 5.5V for TPS2592Bx. The device can continuously sustain a voltage of 20V on VIN pin.

However, above the recommended maximum bus voltage, the device will be in over-voltage protection (OVP)

which can potentially heat up the device and cause thermal shutdown.

dV/dT: Connect a capacitor from this pin to GND to control the slew rate of the output voltage at power-on. This

slew rate at start-up is shown below:

(1)

Where:

(2)

For details on how to select an appropriate charging time/rate, refer to the applications section: "INRUSH

CURRENT AND POWER DISSIPATION DURING START-UP".

BFET: Connect this pin to an external NFET that can be used to disconnect input supply from rest of the system

in the event of power failure at VIN. BFET pin is controlled by either UVLO event or EN/UVLO (see table below).

BFET can source charging current of 2µA (TYP) and sink (discharge) current from the gate of the external FET

via a 26

Ω internal discharge resistor to initiate fast turn-off, typically <1 µs.

Copyright © 2013, Texas Instruments Incorporated

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Product Folder Links: TPS2592Ax TPS2592Bx