Two-channel PCB automatically balances supercapacitors
Advanced Linear Devices has developed the SABM2, a two-channel PCB, that provide production-ready automatic balancing for two-cell supercapacitor, low-voltage systems.
The SABMB2 offers over-voltage protection and low power usage for supercapacitors required in industrial controls, remote monitoring and battery back-up applications.
“The active cell balancing of the SABMB2 is ideally suited for today’s supercapacitors because the impact on power consumption is negligible,” said Robert Chao, president and founder of ALD.
The two-channel supercapacitor automatic balancing (SAB) PCB balances leakage current, manages over-voltage and dissipates zero power. Each SABMB2 balances two supercapacitors used in a series stack. The board can be used for both prototyping or production, and can be used without requiring additional engineering resources, says ADL. The SABMB2 boards are suitable for use in robotics, utility boxes, critical data protection and battery back-up products.
ALD’s SABMB2 two-channel board uses an ALD9100xx dual SAB MOSFET to automatically balance each individual supercapacitor cell in the stack. The board allows system designers and developers to control leakage current and balance voltage in each cell, thus preventing over-voltage damage, explains ADL.
Additionally, the SAB MOSFET’s PCB-balancing technology enables low power operation. The average added power dissipation from the SABMB2 is zero, providing an energy efficiency for low-loss energy applications. In many cases, this added power burn is negative, meaning power usage due to supercapacitor leakage is lowered when these devices are added for balancing. The MOSFETs can save supercapacitor leakage current and associated power dissipation by lowering the operating bias voltage of the leakier of the two supercapacitors.
By offering automatic balancing, each device in the ALD9100XX SAB MOSFET family provides a design alternative that is superior to most passive or active balancing methods, including operational-amp-based schemes.
The SABMB2 is designed to reduce time-to-market in a small package of just 0.6 x 1.0-inch (15.2 x 25.4mm) for easy integration that reduces the bill of material costs, explains ADL. The board can extend the operational life of the stacked supercapacitor, balancing cells ranging from two in a series, up to dozens, and for cells that range from 0.1 to 3000Farad in 3.3, 4.2 and 5.0V systems.
The SABMB2 boards join ADL’s family of supercapacitor-balancing PCBs. The boards are available blank or populated with the ALD9100XX installed at test.
The product can be ordered directly from ALD or from online distributors DigiKey and Mouser.
