Linear Technology has introduced a voltage supply regulator chip that includes an interface to take care of charging, balancing and monitoring external supercaps (or batteries) for system power backup. Its wide 0.1 V to 5.5 V capacitor/battery voltage and 1.8 V to 5.25V system backup voltage ranges make it suitable for a wide range of backup applications using supercapacitors or batteries. A proprietary low noise switching algorithm optimizes efficiency with capacitor/battery voltages that are above, below or equal to the system output voltage.

The LTC3110 can autonomously transition from charge to backup mode or switch modes based on an external command. Pin-selectable Burst Mode operation reduces standby current and improves light-load efficiency, which combined with a 1 μA shutdown current make the LTC3110 ideally suited for backup applications. Additional features include voltage supervisors for charge direction control, end of charge and a general purpose comparator with open-collector output for interfacing with a microcontroller.

Key features of the LTC3110:

• VCAP operating range: 0.1 V to 5.5 V
• VSYS operating range: 1.71 V to 5.25 V
• Automatic switchover from charge to backup mode
• Programmable ±2% accurate charge input current limit from 125 mA to 2 A
• ±1% backup voltage accuracy
• Automatic backup capacitor balancing
• Fixed 1.2 MHz switching frequency
• Burst mode operation: 40 μA quiescent current
• Built-in programmable multipurpose comparator with open-collector output
• Open-collector outputs to indicate direction of operation and end of charge

The LTC3110 is available in thermally enhanced, low profile 24-lead TSSOP and 4 mm × 4 mm QFN packages.