link to page 16 Click here for production status of specific part numbers. MAX388892.5V to 5.5V, 3A Reversible Buck/BoostRegulator for Backup ApplicationsProduct HighlightsSimplified Application Diagram • 2.5V to 5.5V System Output Voltage Range • 0.5V to 5.5V Supercapacitor Voltage Range CHARGE DISCHARGE • ±1% Threshold Accuracy L1 • 2.5% Hysteresis between Backup and Charging 0.47µH VCAP VSYS • 1A to 3A Peak Inductor Current Limit 2.7V (MAX) 3.0V (BACKUP) LX CAP SYS CSC 10F • Peak Inductor Current Is Pin-Programmable C1 R1 R6 R8 R9 C5 SUPER MAIN SYSTEM 22µF 1.82MΩ 1.82MΩ 1MΩ 1MΩ 150µF BATTERY CAP LOAD (REMOVABLE) over 1A to 3A through External Resistor FBCR FBS MAX38889 R2 • 402kΩ 94% Peak Efficiency, Charging or Discharging Mode BKB BACKUP FBCH RDY READY • CHARGE ENABLE ENC 4µA Quiescent Current in Ready State ENB ISET GND PGND • After Supercapacitor Is Charged, Draws only BACKUP ENABLE R3 RISET R7 33kΩ 1.21MΩ 499kΩ 4µA of Quiescent Current • Ready and Backup State Outputs • RDY and BKB Flags Provide Real-Time Status to System • 3mm x 3mm, 16-Pin TQFN Package Pin ConfigurationKey Applications ISET FBS FBCH FBCR 12 11 10 9 • Handheld Industrial Equipment • Portable Devices/Computers with Removable Battery SYS 13 8 LX • Industrial Sensor and Actuators • Aftermarket Automotive Tracking SYS 14 7 LX GND (EXPOSED PAD) PGND 15 6 LX PGND 16 5 CAP 1 2 3 4 ENC ENB RDY BKB 3mm x 3mm, 16 TQFNOrdering Informationappears at end of data sheet. 19-101019; Rev 1; 5/21 Document Outline Product Highlights Key Applications Simplified Application Diagram Pin Configuration Absolute Maximum Ratings Package Information Electrical Characteristics Typical Operating Characteristics Pin Configuration Pin Descriptions Functional Diagram Detailed Description Application Circuits Supercapacitor Voltage Configuration System Voltage Configuration Charge/Discharge Current Configuration Charging Backup Applications Information Capacitor Selection Supercapacitor Selection Inductor Selection Status Flags BKB Flag RDY Flag Enabling the Device Charger Enable Input (ENC) Backup Enable Input (ENB) PCB Layout Guidelines Ordering Information