Advanced Linear Devices ALD910028SALI

SAB MOSFETs are fabricated using production-proven EPAD technology, designed to address voltage and leakage current balancing issues in series-connected supercapacitors. By connecting one or more devices in combination across each supercapacitor bank, leakage current balancing can be achieved for series-connected supercapacitors to prevent overvoltage.

The ALD810028 provides a unique, precise set of operating voltage and current characteristics for each of its four SAB MOSFET devices, capable of balancing up to four series-connected supercapacitors. The ALD910028 provides a unique set of precise operating electrical characteristics for each of its two SAB MOSFET devices, suitable for up to two series-connected supercapacitors.

Each SAB MOSFET features a precise gate threshold voltage in Vt mode. Different VIN levels produce output current characteristics IOUT = IDS(ON), forming an effective variable resistance whose impedance varies exponentially with VIN. When this VIN is connected across each supercapacitor in series, the voltage and current of each supercapacitor can be balanced within its limit range.

When connected across supercapacitors, the voltage-dependent characteristics of the on-resistance of ALD810028/ALD910028 effectively control overvoltage rise across the supercapacitors. In a series-connected supercapacitor bank, the SAB MOSFETs connected across these supercapacitors exhibit complementary reverse current levels, generating negligible additional leakage current beyond that produced by the supercapacitors themselves.

• Simple and cost-effective to use
• Factory precision trimmed
• Automatic leakage current regulation and balancing
• Effective supercapacitor charge balancing
• Balance up to 4 supercapacitors in a single IC package
• Compatible with 2-cell, 3-cell, and 4-cell series configurations
• Scalable to larger supercapacitor banks and arrays
• Near-zero additional leakage current
• Zero leakage current at 0.3V below rated voltage
• Balance supercapacitors in series and/or parallel connections
• Leakage current is an exponential function of cell voltage
• Active current range from < 0.3nA to > 1000μA
• Always active with fast response time
• Minimizes leakage current and power consumption

• Leakage current balancing for series supercapacitor cells
• Energy harvesting
• Long-term backup battery with supercapacitor output
• Zero-power voltage divider at selected voltage
• Matched current mirrors and current sources
• Maximum voltage limiter in zero-power mode
• Scalable supercapacitor banks and arrays