1FEATURES

• Wide Input Supply Voltage Range:

4.5 V - 18 V

• 0.8-V, 1% Accuracy Reference

• Continuous Loading:

3 A (Buck1), 2 A (Buck2 and 3)

• Maximum Current:

3.5 A (Buck 1), 2.5 A (Buck2 and 3)

• 300-kHz – 2.2-MHz Switching Frequency Set

By External Resistor

• External Enable Pins With Built-In Current

Source for Easy Sequencing

• External Soft Start Pins

• Adjustable Cycle-by-Cycle Current Limit Set

by External Resistor

• Current-Mode Control With Simple

Compensation Circuit

• Pulse Skipping Mode to Achieve High Light

Load Efficiency, Allowing for an Output Ripple

Better than 2%

• Forced PWM Mode

• Support Pre-Biased Outputs

• Power Good Supervisor and Reset Generator

• 2 USB Power Switches current limiting at

typical 1.2A (0.8/1.0/1.4/1.6/1.8/2.0/2.2A

Available with Manufacture Trim Options)

• Small, Thermally Efficient 40-Pin 6-mm x 6-mm

RHA (QFN) package

• -40°C to 125°C Junction Temperature Range

DESCRIPTION/ORDERING INFORMATION

TPS65288 is a power management IC with three step-down buck converters. Both high-side and low-side

MOSFETs are integrated to provide fully synchronous conversion with higher efficiency. The converters are

designed to simplify its application while giving the designer the option to optimize their usage according to the

target application.

The converters can operate in 5-, 9-, 12- or 15-V systems. The output voltage can be set externally using a

resistor divider to any value between 0.8 V and the input supply minus the resistive drops on the converter path.

Each converter features enable pin that allows a delayed start-up for sequencing purposes, soft start pin that

allows adjustable soft-start time by choosing the soft-start capacitor, and a current limit (RLIM) pin that enables

designer to adjust current limit by selecting an external resistor and optimize the choice of inductor. All converters

operate in ‘hiccup mode’: Once an over-current lasting more than 10 ms is sensed in any of the converters, they

will shut down for 10 ms and then the start-up sequencing will be tried again. If the overload has been removed,

the converter will ramp up and operate normally. If this is not the case the converter will see another over-current

event and shuts down again repeating the cycle (hiccup) until the failure is cleared. If an overload condition lasts

for less than 10 ms, only the relevant converter affected will shut-down and re-start and no global hiccup mode

will occur.

The switching frequency of the converters is set by an external resistor connected to ROSC pin. The switching

regulators are designed to operate from 300 kHz to 2.2 MHz. The converters operate with 180° phase between

then to minimize the input filter requirements. All converters have peak current mode control which simplifies

external frequency compensation.

The device has a built-in slope compensation ramp. The slope compensation can prevent sub harmonic

oscillations in peak current mode control. A traditional type II compensation network can stabilize the system and

achieve fast transient response. Moreover, an optional capacitor in parallel with the upper resistor of the

feedback divider provides one more zero and makes the crossover frequency over 100 kHz.

All converters feature an automatic low power pulse skipping mode (PSM) which improves efficiency during light

loads and standby operation, while guaranteeing a very low output ripple, allowing for a value of less than 2% at

low output voltages.