How to realize the supercapacitor fully depleted power (I)

When a supercapacitor is charged for a standby power system such as a solid-state drive (SSD) or a portable medical system, the value, size and cost of the supercapacitor are proportional to the required holding time. Once the user removes the system from the input power and switches to the super capacitor, your system needs minimal running time. The purpose is to make the size of the supercapacitor just enough to power the system when your system writes key information to non-volatile memory and closes the time it takes. But sizing the supercapacitor is not your only challenge.

Because the voltage of the super capacitor will change, the power supply between the super capacitor and the system power supply voltage rail is needed. Since the rated voltage of the supercapacitor is usually only a few volts, a step-up converter is needed to raise the voltage to 3.3V, 5V or 12V system rail. If you just want to let your own supercapacitor discharge to 2.5V, then this two-way standby power solution will be very suitable for placing between the supercapacitor and the system rails.