The ALD810016 from Advanced Linear Devices is a part of the ALD8100xx family of Supercapacitor Auto Balancing (SAB) MOSFETs. This innovative solution is designed to address the critical challenges of voltage and leakage-current balancing in series-connected supercapacitors. By utilizing one or more devices connected across each supercapacitor stack, over-voltages can be prevented, ensuring optimal performance.

One of the standout advantages of the ALD810016 is its near-zero additional leakage currents and zero leakage at 0.3V below rated voltages, resulting in minimal power loss. By effectively balancing series and parallel-connected supercaps, these MOSFETs provide a reliable solution for a wide range of applications.

Featuring a precision gate threshold voltage in the Vt mode, the SAB MOSFETs ensure accurate voltage regulation. When the gate-drain source terminals (VGS = VDS) are connected at a drain-source current of IDS(ON) = 1µA, the gate threshold voltage is set at 1.60V. Different input voltages (VIN = VGS = VDS) generate an Output Current IOUT = IDS(ON), resulting in an effective variable resistor that exponentially varies with VIN. This configuration enables precise balancing of each supercapacitor within its voltage and current limits.

For instance, when VIN = 1.60V is applied, the corresponding IOUT is 1µA. Increasing VIN by 100mV to 1.70V results in a tenfold increase in IOUT. Further increasing VIN to 1.84V leads to a hundredfold increase in IOUT, reaching 100µA. Conversely, decreasing VIN by 100mV to 1.50V reduces IOUT to one-tenth of its previous value, which is 0.1µA. Another 100mV decrease in input voltage further reduces IOUT to 0.01µA. Thus, when an ALD810016 SAB MOSFET is connected across a supercapacitor charging to less than 1.40V, it dissipates virtually no power.

The ALD810016 SAB™ MOSFETs are used in a variety of areas, including series-connected supercapacitor cell leakage balancing, energy harvesting systems, long-term backup batteries utilizing supercapacitor outputs, zero-power voltage dividers at selected voltages, matched current mirrors and current sources, and zero-power mode maximum voltage limiters. Moreover, they can be scaled to accommodate larger supercap stacks and arrays, ensuring versatility in different setups.

Available to order at Digi-Key and Mouser (product number ALD810016SCLI) in 16-pin SOIC packages starting at $5.58 each per 50.