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