PCBs protect supercapacitors in industrial control and remote monitoring

The SABMB2 offers over-voltage protection and ultra-low power usage for supercapacitors required in industrial controls, remote monitoring and battery backup applications, says the company.

The two-channel supercapacitor automatic balancing (SAB) PCB balances leakage current, manages over-voltage and dissipates zero power. Each board balances two supercapacitors used in a series stack. It can be used for both prototyping or production, and does not require additional engineering resources before being used in a variety of applications, from robotics to utility boxes, and critical data protection as well as battery backup products.

Each two-channel board uses an ALD9100xx dual SAB MOSFET to automatically balance individual supercapacitor cells in the stack. According to the company, it allows system designers and developers to control leakage current and balance voltage in each cell, to prevent over-voltage damage.

The MOSFET’s PCB-balancing technology enables low power operation, with average added power dissipation from the SABMB2 at zero. In many cases, the added power burn is negative, meaning power usage due to supercapacitor leakage is lowered when they 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.

Robert Chao, president and founder of ALD, explains: “The active cell balancing of the SABMB2 is ideally suited for today’s supercapacitors because the impact on power consumption is negligible.”

According to the company, by offering automatic balancing, each device in the ALD9100XX SAB MOSFET family provides a design alternative 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 15 x 24.5mm (0.6 x 1.0-inch). It can extend the operational life of the stacked supercapacitor, balancing cells ranging from two to dozens in a series, and for cells that range from 0.1 to 3000F in 3.3, 4.2 and 5.0V systems. 

The boards are available as blank boards or populated with the ALD9100XX installed at test. The product can be ordered directly from the company or from distributors DigiKey and Mouser.