Innovative eFuse charger IC protects supercapacitor back-up power storage devices
The LS0502SCD33 from Littelfuse provides an integrated, high-voltage solution for charging and protecting supercapacitors used to back-up battery power supplies in handheld and portable devices.
Littelfuse has released an eFuse protection IC, the LS0502SCD33, which integrates an advanced charging circuit for a supercapacitor with protection against electrical faults, all in a single chip.Ā
In many applications in which back-up power is required, the narrow temperature range of lithium-ion batteries limits their use. A supercapacitor-based solution offers a wider operating-temperature range, high power output and high energy density.
The LS0502SCD33 performs the functions of both charging and protecting any such supercapacitor-based back-up power system. It can operate at high voltages of more than 3 V without the need for complex power management systems. The LS0502SCD33 safeguards the system from potential damage by integrating input over-voltage and over-current protection, providing designers with a flexible, integrated, and compact storage capacitor or capacitor-bank back-up solution.Ā
When the main supply is present, and above the minimum system supply voltage, the host system will draw power from it. At the same time, an integrated linear charger in the LS0502SCD33 charges the storage element at a current of up to 300 mA. Once the storage element is charged, the circuit draws only 2.5 Ī¼A while it maintains the supercapacitor in its ready state.Ā
When the main supply is removed, the integrated reverse blocking switch will block current flow from the system rail to the input. The linear charger will be turned on to supply the system rail from the supercapacitor with up to 2 A. An integrated cell-balancing circuit monitors the cell voltages when charging a dual-cell supercapacitor, and keeps the two cellsā voltage the same.