Advanced Linear Devices (ALD), a California manufacturer of analog technology, has created a six-channel supercapacitor automatic balancing (SAB) printed circuit board (PCB). ALD says the board, known as SABMB6, can balance any size supercapacitor with zero added power dissipation.
Each PCB can balance up to six supercapacitors stacked in a series, ranging from six to hundreds of supercapacitors with capacities from 0.1 to 3,000 Farads in 12 volts and higher. ALD says the ultra-low power dissipation enables energy-efficient supercapacitor balancing.
ALD president Robert Chao said, “Rather than focusing on the DC voltage balancing, the ALD method manages leakage current and is independent of the cell capacitance.”
ALD notes that battery developers are increasingly using six 2 V cells for 12 V applications, which often requires developers to stack supercapacitors in series or in parallel. By allowing up to six connected cells, ALD says the SABMB6 reduces the risk of a short circuit and battery failure.
Each six-channel PCB uses three SAB MOSFETs that automatically balance the leakage and voltage of each supercapacitor cell connected in series. Reverse-biased external clamping power diodes (Schottky rectifiers) can be installed when necessary across each SAB MOSFET to clamp surge current transients.
ALD already manufactures two- and four-channel SAB PCBs, and the boards can be cascaded with mix-and-match configurability to balance multiple series stacks.