Datasheet

TPS62260, TPS62261

TPS62262, TPS62263

www.ti.com

SLVS763D –JUNE 2007– REVISED FEBRUARY 2011

ENABLE

The device is enabled setting EN pin to high. During the start up time t

Start Up

the internal circuits are settled and

the soft start circuit is activated. The EN input can be used to control power sequencing in a system with various

DC/DC converters. The EN pin can be connected to the output of another converter, to drive the EN pin high and

getting a sequencing of supply rails. With EN = GND, the device enters shutdown mode in which all internal

circuits are disabled. In fixed output voltage versions, the internal resistor divider network is then disconnected

from FB pin.

SOFT START

The TPS62260 has an internal soft start circuit that controls the ramp up of the output voltage. The output

voltage ramps up from 5% to 95% of its nominal value within typical 250μs. This limits the inrush current in the

converter during ramp up and prevents possible input voltage drops when a battery or high impedance power

source is used. The soft start circuit is enabled within the start up time t

Start Up

SHORT-CIRCUIT PROTECTION

The High Side and Low Side MOSFET switches are short-circuit protected with maximum switch current = I

LIMF

The current in the switches is monitored by current limit comparators. Once the current in the High Side

MOSFET switch exceeds the threshold of it's current limit comparator, it turns off and the Low Side MOSFET

switch is activated to ramp down the current in the inductor and High Side MOSFET switch. The High Side

MOSFET switch can only turn on again, once the current in the Low Side MOSFET switch has decreased below

the threshold of its current limit comparator.

THERMAL SHUTDOWN

As soon as the junction temperature, T

, exceeds 140°C (typical) the device goes into thermal shutdown. In this

mode, the High Side and Low Side MOSFETs are turned-off. The device continues its operation when the

junction temperature falls below the thermal shutdown hysteresis.

Product Folder Link(s): TPS62260 TPS62261 TPS62262 TPS62263