ALD adds over-voltage protection to boost supercapacitor reliability
Advanced Linear Devices (ALD) has added over-voltage protection to the dual-channel SABMBOVP2XX family of supercapacitors.
The supercapacitors can be used for applications that require balancing, such as automotive, transportation, automation, data centres and power grids.
According to Robert Chao, president and founder of ALD: “The OVP board is the only commercially available balancing scheme that manages both over-voltage and leakage current. The circuit used on the board offers matched precision push-pull voltage/current action, which is ideal for cells with a minimal amount of energy loss.”
The SABMBOVP2XX PCBs enable precision voltage clamp circuits with high current gains to balance large supercapacitors that are stacked in a series, from two to hundreds of cells with values of 0.1F to 3,000F and above.
The SABMBOVP family has low output currents at input voltages that are below the threshold voltage when a drastic change in output current balancing is achieved through a sharp and steep change in the output current in response to small, incremental input voltages that are above the threshold voltage and balancing occurs.
The supercapacitors have a high current gain (dl/dV of approximately 3mA/1mV) amplifier, which typically produces more than 1,000,000 times the output increase with very small increments of less than 100mV in input change.
The SABMBOVP devices specifically target cells in which the charging/discharging currents can be up to 1,000A, and charging at a few mA will take too long to reach the supercapacitor’s voltage limits.
The SABMBOVP2XX PCB is populated with one of the company’s ALD9100XXSALI Supercapacitor Auto Balancing (SAB) MOSFETs, which specify the circuit threshold or clamping voltage to balance the circuit with near-zero charge loss. The balancing output current from the SAB MOSFET is amplified to produce (nominally) 1mA of balancing output current at Vin, which is equal to the rated SAB MOSFET threshold.
The PCBs measure just 0.6 x 1.6 inches (15.24 x 40.64mm), and operate in the industrial temperature range of -40 to +85°C.
It is made with RoHS-compliant FR4 material and supplied ready for mounting a single ALD9100XX, eight-lead SOIC.