Backup power manager for supply rails
Linear Technology Corp.’s LTC4040 is a lithium battery backup power management system for 3.5 V to 5 V supply rails that must be kept active during a main power failure. The LTC4040 uses an on-chip bidirectional synchronous converter to provide high efficiency battery charging as well as high current, high efficiency backup power. When external power is available, the device operates as a step-down battery charger for single-cell Li-Ion or LiFePO4 batteries while giving preference to the system load. When the input supply drops below the adjustable power-fail input (PFI) threshold the LTC4040 operates as a step-up regulator designed to deliver up to 2.5 A to the system output from the backup battery. The LTC4040 is designed for applications such as fleet and asset tracking, automotive GPS data loggers, automotive telematics systems, toll collection systems, security systems, communications systems, industrial backup, and USB-powered devices.
Its adjustable input current limit function enables operation from a current limited source while prioritizing system load current over battery charge current. An external disconnect switch isolates the primary input supply from the system during backup. The LTC4040’s 2.5 A battery charger provides eight selectable charge voltages optimized for Li-Ion and LiFePO4 batteries. The device also includes input current monitoring, an input power loss indicator and a system power loss indicator. The device operates from -40 C to 125 C in both E and I grades.
Linear Technology Corp.
– Edited by CFE Media. See more Control Engineering energy and power products.