Advanced Linear Devices Inc. (ALD) has announced the immediate availability of universal printed circuit boards (PCB) designed to automatically balance leakage currents and manages over voltage enabling ultra-low power usage in supercapacitors used in a series stack. The board uses ALD’s SAB MOSFETs to balance the leakage current in each individual supercapacitor cells, even for cells of 3000 Farad (F) or more.
The PCB is designed to allow system engineers to test, evaluate, prototype or use in production products. Supercapacitor balancing is required by cell manufacturers when used in stacks of two or more. Balancing manages over-voltage limits, a main cause of product failures. Additionally, the SAB MOSFET’S PCB balancing technology reduces leakage current enabling ultra-low power operation.
Each device in the ALD8100XX/ALD9100XX SAB MOSFET provides a superior circuit design alternative to passive or active balancing methods by offering automatic active leakage current regulation, and a space and cost-saving alternative to op-amp based balancing schemes.
The SABMB16/SABMB810025/SABMB910025 are universal application boards. The first two versions in the series are SABMB810025 and SABMB910025. These are 2.5-volt universal boards allowing designers to select either the ALD810025 SAB MOSFETs or the ALD910025 SAB MOSFETs installed. A third version is unpopulated to allow engineers to select the appropriate SAB MOSFETs based on their specific design specifications. All three options are delivered ready to use, designed for compact, economical and effective balancing any size supercapacitors with little or no power dissipation. . No user circuit design or hardware engineering is necessary.
The charging or discharging of supercapacitor currents pass through the supercapacitors themselves, but do not pass through the SABMB16 boards or SAB MOSFETs mounted on the PCB board. In many cases, the total additional leakage current contributed by the PCB is approximately zero, or no more than a small percentage of the highest supercapacitor cell leakage current in the stack. This contrasts with other methods of balancing where the additional power dissipation used by the balancing circuitry far exceeds the supercapacitor power burn caused by its own leakage current.
SABMB16 is designed for ease of use as a plug ,and play PCB for supercapacitors of 0.1 farad (F) to 3,000 F and beyond. The average additional power dissipation due to DC leakage of the supercapacitor is zero, which suits this method of supercapacitor balancing for low-loss energy harvesting and long-life battery operated applications.
Products can be ordered directly from ALD or ordered from DigiKey or Mouser. Quantities start at $33.34 for a single unit.