ENABLE

SOFT START

SHORT-CIRCUIT PROTECTION

THERMAL SHUTDOWN

TPS62560

TPS62561, TPS62562

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 terminal can be connected to the output of another converter, to drive the

EN terminal high to achieve a sequencing of the given 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 the FB terminal.

The TPS62560 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 typically within 250

µs. This limits the inrush current into

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

The current in the switches is monitored by current-limit comparators. Once the current in the high-side MOSFET

switch exceeds the threshold of its 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 after the current in the low-side MOSFET switch has decreased below the threshold of its

current-limit comparator.

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.

16

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