ALD810023 Datasheet | Advanced Linear Devices

DESCRIPTION The ALD810023/ALD910023 are members of the ALD8100xx (quad) and ALD9100xx (dual) family of Supercapacitor Auto Balancing MOSFETs, or SAB™ MOSFETs. SAB MOSFETs are built with production proven EPAD® technology and are designed to address voltage and leakage-current balancing of supercapacitors connected in series. Supercapacitors, also known as ultracapacitors or supercaps, connected in series can be leakage-current balanced by using a bination of one or more devices connected across each supercapacitor stack to prevent over-voltages. The ALD810023 offers a set of unique, precise operating voltage and current characteristics for each of four SAB MOSFET devices, as shown in its Operating Electrical Characteristics table. It can be used to balance up to four supercapacitors connected in series. The ALD910023 has its own set of unique precision Operating Electrical Characteristics for each of its two SAB MOSFET devices, suitable for up to two series-connected supercapacitors. Each SAB MOSFET features a precision gate threshold voltage in the Vt mode, which is 2.30V when the gate-drain source terminals (VGS = VDS) are connected together at a drain-source current of IDS(ON) = 1µA. In this mode, input voltage VIN = VGS = VDS. Different VIN produces an Output Current IOUT = IDS(ON) characteristic and results in an effective variable resistor that varies in value exponentially with VIN. This VIN, when connected across each supercapacitor in a series, balances each supercapacitor to within its voltage and current limits. When VIN = 2.30V is applied to an ALD810023/ALD910023, its IOUT is 1µA. For a 100m V increase in VIN, to 2.40V, IOUT increases by about tenfold. For an additional increase in VIN to 2.52V for the ALD910023 (2.54V for the ALD810023), IOUT increases one hundredfold, to 100µA. Conversely, for a 100m V decrease in VIN to 2.20V, IOUT decreases to one tenth of its previous value, to 0.1µA. Another 100m V decrease in input voltage would reduce IOUT to...