Analog Devices LTC3351 is a synchronous step-down controller that charges and monitors up to four supercapacitors at the same time. The converter drives n-channel mosfet constant current/constant voltage charging with programmable input current limitation. In addition, the device operates in reverse as a step-up converter to transfer power from the supercapacitor bank to the backup power rail. The internal balancer eliminates the need for external balancing resistors, and each capacitor has a shunt regulator for overvoltage protection.
Typical application
Pin configuration
The LTC3351 monitors the system voltage, current, stack capacitance and ESR, which can be read through the I (2) C/SMBus port. The heat exchange controller uses an n-channel mosfet for burst control and a low loss path from input to output. An ideal diode controller uses the n-channel MOSFET's low loss power path from the supercapacitor to the output. The device is packaged with 44 pin QFN, and the operating temperature is - 40 ° C to+125 ° C. The LTC3351 is designed for hot plug applications such as PCIe cards, high current UPS systems and servers.
Block diagram
