4-Switch buck-boost bi-directional DC-DC converter reference design


Design files


This DC-DC power converter reference design demonstrates a novel approach for battery backup applications. During normal operation, the converter works as a battery charger with CC-CV-Topping charging algorithm compatible for lithium-ion batteries. When DC bus power is lost, the converter immediately changes to backup operation to seamlessly provide power to the system. Once the DC bus power recovers, the converter automatically switches back to battery charge mode. The battery voltage can be higher or lower than DC bus voltage. Depending on the DC bus and battery voltage, the converter operates as either a synchronize buck or a synchronize boost converter in which only two switches are switching, switching loss is reduced and high effieciency is achieved. Only when DC bus and battery voltage are close to each other, then the converter operates as a buck-boost converter.

  • Multi-mode control to reduce switching loss and achieve high efficiency
  • Built-in battery charging CC-CV topping algorithm compatible for lithium-ion and lithium-polymer battery
  • Ultra-fast changeover from charging to backup supply mode enables seamless power transfer during power failure
  • DC-bus voltage can be higher or lower than battery voltage
  • Battery over voltage and over current protection, DC bus over voltage protection
Output voltage options PMP21529.1
Vin (Min) (V) 35
Vin (Max) (V) 55
Vout (Nom) (V) 38
Iout (Max) (A) 2
Output Power (W) 76
Isolated/Non-Isolated Non-Isolated
Input Type DC
Topology Buck Boost- 4 Switch
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A fully assembled board has been developed for testing and performance validation only, and is not available for sale.

Design files & products

Design files

Download ready-to-use system files to speed your design process.

TIDT046.PDF (804 K)

Test results for the reference design, including efficiency graphs, test prerequisites and more

TIDRY12.PDF (276 K)

Detailed schematic diagram for design layout and components

TIDRY13.PDF (105 K)

Complete listing of design components, reference designators, and manufacturers/part numbers

TIDRY14.PDF (281 K)

Detailed overview of design layout for component placement

TIDRY16.ZIP (1503 K)

Files used for 3D models or 2D drawings of IC components

TIDCF34.ZIP (679 K)

Design file that contains information on physical board layer of design PCB

TIDRY15.PDF (1520 K)

PCB layer plot file used for generating PCB design layout


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Technical documentation

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Type Title Date
* Test report 4-Switch Buck-Boost Bi-directional DC-DC Converter Reference Design Dec. 12, 2018

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