TPS65288

ACTIVE

4.5V to 18V input, 3A/2A/2A triple synchronous buck converter with dual load switches

Product details

Rating Catalog Operating temperature range (°C) -40 to 125 Topology Buck Iout (max) (A) 3 Vin (min) (V) 4.5 Vin (max) (V) 18 Switching frequency (min) (kHz) 300 Switching frequency (max) (kHz) 2200 Features Adjustable current limit, Enable, Light-load efficiency, Power good, Prebias startup, Soft-start adjustable, Synchronous rectification, UVLO adjustable Vout (min) (V) 0.8 Vout (max) (V) 17 Iq (typ) (µA) 700
Rating Catalog Operating temperature range (°C) -40 to 125 Topology Buck Iout (max) (A) 3 Vin (min) (V) 4.5 Vin (max) (V) 18 Switching frequency (min) (kHz) 300 Switching frequency (max) (kHz) 2200 Features Adjustable current limit, Enable, Light-load efficiency, Power good, Prebias startup, Soft-start adjustable, Synchronous rectification, UVLO adjustable Vout (min) (V) 0.8 Vout (max) (V) 17 Iq (typ) (µA) 700
VQFN (RHA) 40 36 mm² 6 x 6
  • 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 × 6-mm RHA (QFN) package
  • –40°C to 125°C Junction Temperature Range

  • 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 × 6-mm RHA (QFN) package
  • –40°C to 125°C Junction Temperature Range

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.

The device incorporates an overvoltage transient protection circuit to minimize voltage overshoot. The OVP feature minimizes the output overshoot by implementing a circuit to compare the FB pin voltage to OVP threshold which is 106% of the internal voltage reference. If the FB pin voltage is greater than the OVTP threshold, the high side MOSFET is disabled preventing current from flowing to the output and minimizing output overshoot. When the FB voltage drops lower than the OVP lower threshold which is 104%, the high side MOSFET is allowed to turn on the next clock cycle.

TPS65288 features a supervisor circuit which monitors each buck’s output and the PGOOD pin is asserted once sequencing is done. The PGOOD pin is an open drain output. The PGOOD pin is pulled low when any buck converter is pulled below 85% of the nominal output voltage. The PGOOD is pulled up when all converter outputs are more than 90% of its nominal output voltage. The default reset time is 100 ms. The polarity of the PGOOD is active high.

The 2 USB switches provide up to 1.2A of current as required by downstream USB devices. When the output load exceeds the current-limit threshold or a short is present, the PMU limits the output current to a safe level by switching into a constant-current mode and pulling the over current logic output low. When continuous heavy overloads or short circuits increase the power dissipation in the switch, causing the junction temperature to rise, a thermal warning protection circuit shuts off the USB switch and allows the buck converters to carry on operating.

The device implements an internal thermal shutdown to protect itself if the junction temperature exceeds 160°C. The thermal shutdown forces the device to stop operating when the junction temperature exceeds thermal trip threshold. Once the die temperature decreases below 140°C, the device reinitiates the power up sequence. The thermal shutdown hysteresis is 20°C.

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.

The device incorporates an overvoltage transient protection circuit to minimize voltage overshoot. The OVP feature minimizes the output overshoot by implementing a circuit to compare the FB pin voltage to OVP threshold which is 106% of the internal voltage reference. If the FB pin voltage is greater than the OVTP threshold, the high side MOSFET is disabled preventing current from flowing to the output and minimizing output overshoot. When the FB voltage drops lower than the OVP lower threshold which is 104%, the high side MOSFET is allowed to turn on the next clock cycle.

TPS65288 features a supervisor circuit which monitors each buck’s output and the PGOOD pin is asserted once sequencing is done. The PGOOD pin is an open drain output. The PGOOD pin is pulled low when any buck converter is pulled below 85% of the nominal output voltage. The PGOOD is pulled up when all converter outputs are more than 90% of its nominal output voltage. The default reset time is 100 ms. The polarity of the PGOOD is active high.

The 2 USB switches provide up to 1.2A of current as required by downstream USB devices. When the output load exceeds the current-limit threshold or a short is present, the PMU limits the output current to a safe level by switching into a constant-current mode and pulling the over current logic output low. When continuous heavy overloads or short circuits increase the power dissipation in the switch, causing the junction temperature to rise, a thermal warning protection circuit shuts off the USB switch and allows the buck converters to carry on operating.

The device implements an internal thermal shutdown to protect itself if the junction temperature exceeds 160°C. The thermal shutdown forces the device to stop operating when the junction temperature exceeds thermal trip threshold. Once the die temperature decreases below 140°C, the device reinitiates the power up sequence. The thermal shutdown hysteresis is 20°C.

Download View video with transcript Video

Technical documentation

star =Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 2
Type Title Date
* Data sheet 4-5V-19-V Input, High Current, Syncronous Step Down 3 DC-DC Converters .. datasheet 17 May 2013
EVM User's guide TPS65288 EVM User Guide 10 May 2013

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Package Pins CAD symbols, footprints & 3D models
VQFN (RHA) 40 Ultra Librarian

Ordering & quality

Information included:
  • RoHS
  • REACH
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring
Information included:
  • Fab location
  • Assembly location

Support & training

TI E2E™ forums with technical support from TI engineers

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​

Videos