Linear Technology Corporation introduces the LTC3643, a bidirectional, high voltage boost capacitor charger that automatically converts to a buck regulator for system backup. The proprietary, single-inductor topology with integrated PowerPath™ functionality does the work of two separate switching regulators, reducing size, cost and complexity. The LTC3643 operates in two modes – boost charge mode and buck backup mode. The charging mode efficiently charges an electrolytic capacitor array up to 40V with an internal switch current rating of 2A from an input supply between 3V to 17V. In backup mode, when the input supply falls below the programmable power-fail (PFI) threshold, the step-up charger operates in reverse as a synchronous step-down regulator to power and hold up the system rail from the backup capacitor. During backup, the current limit can be programmed from 2A to 4A, making this device ideal for high energy, relatively short duration backup capacitor systems, power failure backup systems, solid-state drives and battery stack charging applications.
LTC3643 – 2A Bidirectional Power Backup Supply – [Link]