Click here for production status of specific part numbers. MAX38889 2.5V to 5.5V, 3A Reversible Buck/Boost Regulator for Backup Applications Product Highlights Simplified Application Diagram 2.5V to 5.5V System Output Voltage Range CHARGE DISCHARGE 0.5V to 5.5V Supercapacitor Voltage Range L1 1% Threshold Accuracy 0.47H 2.5% Hysteresis between Backup and Charging VCAP VSYS 2.7V (MAX) 3.0V (BACKUP) LX 1A to 3A Peak Inductor Current Limit CAP SYS CSC 10F C1 R1 MAIN R6 R8 R9 C5 SYSTEM SUPER Peak Inductor Current Is Pin-Programmable 22F BATTERY 1.82M 1.82M 1M 1M 150F LOAD CAP (REMOVABLE) FBCR FBS over 1A to 3A through External Resistor MAX38889 R2 402k BKB BACKUP 94% Peak Efficiency, Charging or Discharging Mode FBCH RDY READY CHARGE ENABLE ENC 4A Quiescent Current in Ready State ENB ISET GND PGND RISET R7 BACKUP ENABLE R3 After Supercapacitor Is Charged, Draws only 33k 1.21M 499k 4A 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 Configuration Key Applications 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 3mm x 3mm, 16 TQFN Ordering Information appears at end of data sheet. 19-101019 Rev 1 5/21 ENC ISET ENB FBS RDY FBCH BKB FBCR MAX38889 2.5V to 5.5V, 3A Reversible Buck/Boost Regulator for Backup Applications Absolute Maximum Ratings CAP, ENB, ENC to GND .............................. -0.3V to +6V Operating Temperature Range ........... -40C to +125C SYS, BKB, RDY to GND .............................. -0.3V to +6V Storage Temperature Range ............... -65C to +150C FBCH, FBCR to GND .................... -0.3V to CAP + 0.3V Maximum Junction Temperature ........................ +150C FBS, ISET to GND .......................... -0.3V to SYS + 0.3V Lead Temperature (soldering, 10 seconds) ..... +300C PGND to GND ............................................. -0.3V to +0.3V Soldering Temperature (reflow)........................... +260C Continuous Power Dissipation (T = +70C, TQFN, LX RMS Current .................................................. 5.0A A RMS derate 23.1mW/C above +70C) ................ 1847.6mW Output Short-Circuit Duration ...................... Continuous Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Package Information TQFN Package Code T1633+5C Outline Number 21-0136 Land Pattern Number 90-0032 THERMAL RESISTANCE, FOUR-LAYER BOARD Junction to Ambient ( ) 43.3C/W JA Junction to Case ( ) 4C/W JC For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a +, , or - in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four- layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal- tutorial. www.maximintegrated.com Maxim Integrated 2