LTC3643IUDD#PBF

LTC3643 is a bidirectional synchronous step-up charger and step-down converter which efficiently charges a capacitor array upto 40V from an input supply between 3V to 17V. When the input supply falls below the programmable power-fail threshold, the step-up charger operates in reverse as a synchronous step-down regulator to power the system rail from the backup capacitor during this power interruption/failure condition. When charging the backup capacitor, an external low value sense resistor may be used to maintain an accurate current limit from the input supply or implement PowerPath™ functionality. The step-down converter operates at a 1MHz switching frequency, allowing small external components to be used. Low quiescent current during regulation maximizes the energy usage from the backup capacitor. It is used in applications such as backup capacitor systems, power failure backup systems, solid-state drives etc.

• Upto 40V capacitor voltage storage for high energy backup
• Switch C on resistance is 150Mohm typical at (VBOOST = 8.3V, TJ = 25°C)
• Switch A on resistance is 50Mohm typical at (VCAP <gt/>= VIN, TJ = 25°C)
• Switch B on resistance is 75Mohm typical at (VINTVCC = 3.3V, TJ = 25°C)
• Input current limit during charging
• ±1% reference accuracy for system voltage regulation
• Indicator outputs for charge status and input power fail
• Input quiescent current is 800µA typical at (TJ = 25°C, VIN = 5V, VRUN = 2V)
• Operating junction temperature is -40°C to 125°C
• Package style is 24-lead plastic QFN

Notes

ADI products are only authorized (and sold) for use by the customer and are not to be resold or otherwise passed on to any third party