LTC1479 PowerPath Controller for Dual Battery Systems DESCRIPTION FEATURES n Complete Power Path Management for Two The LTC 1479 is the heart of a total power management Batteries, DC Power Source, Charger and Backup solution for single and dual battery notebook computers n Compatible with Li-Ion, NiCd, NiMH and Lead-Acid and other portable equipment. The LTC1479 directs power Battery Chemistries from up to two battery packs and a DC power source to the n 3-Diode Mode Ensures Powers is Available input of the main system switching regulator. It works in under Cold Start Conditions concert with related LTC power management products n All N-Channel Switching Reduces Power Losses (e.g. LTC1435, LT 1511, etc.) to create a total system n Capacitor and Battery Inrush Current Limited solution starting from the batteries and the DC power n Seamless Switching Between Power Sources source, and ending at the input of each of the computers n Independent Charging and Monitoring of Two complex loads. A system-provided power management Battery Packs P monitors and actively directs the LTC1479. n New, Small Footprint, 36-Lead SSOP Package The LTC1479 uses low loss N-channel MOSFET switches U to direct power from three main sources. An adaptive APPLICATIONS current limiting scheme reduces capacitor and battery n Notebook Computer Power Management inrush current by controlling the gates of the MOSFET n Portable Instruments switches during transitions. The LTC1479 interfaces di- n Handheld Terminals rectly to the LT1510, LT1511 and LT1620/LTC1435 bat- n Portable Medical Equipment tery charging circuits. n Portable Industrial Control Equipment , LTC and LT are registered trademarks of Linear Technology Corporation. PowerPath is a trademark of Linear Technology Corporation. TYPICAL APPLICATION TM Dual Battery PowerPath Controller System Block Diagram SW A/B DCIN AC ADAPTER HIGH EFFICIENCY SW C/D R DC/DC SWITCHING SENSE REGULATOR 5V + (LTC1435/LTC1438 SW E/F BAT1 C IN ETC.) SW G SW H BAT2 BATTERY CHARGER BACKUP (LT1510/LT1511/ REGULATOR LT1620/LTC1435) (LT1304) POWER LTC1479 STATUS & MANAGEMENT PowerPath CONTROLLER CONTROL P 1479 TA01 1 U ULTC1479 ABSOLUTE MAXIMUM RATINGS PACKAGE/ORDER INFORMATION DCIN, BAT1, BAT2 Supply Voltages.......... 0.3V to 32V TOP VIEW + + ORDER PART SENSE , SENSE , V , V ..................... 0.3V to 32V BAT 1 36 V DCIN BKUP NUMBER GA, GB, GC, GD, GE, GF, GG, GH .............. 0.3V to 42V 2 35 BAT1 DCDIV SAB, SCD, SEF, SG, SH ............................ 0.3V to 32V LOBAT 3 34 BAT2 SW, V ................................................... 0.3V to 42V LTC1479CG GG GA 4 33 BDIV DCDIV, BDIV ............................................ 0.3V to 5.5V SAB 5 32 V LTC1479IG BAT All Logic Inputs (Note 1).......................... 0.3V to 7.5V GB 6 31 CHGMON All Logic Outputs (Note 1) ....................... 0.3V to 7.5V GC 7 30 BATSEL SCD 8 29 GG V Regulator Output Current................................ 1mA CC GD 9 28 SG V Regulator Output Current .............................. 1mA CCP + GE 10 27 GH V Output Current.................................................. 1mA SEF 11 26 SH V Regulator Output Current ............................ 100A GG GF 12 25 DCINGOOD Operating Temperature + SENSE 13 24 DCIN/BAT LTC1479CG ............................................. 0C to 70C SENSE 14 23 BATDIS LTC1479IG ........................................ 40C to 85C V 15 22 3DM CC Junction Temperature........................................... 125C V 16 21 CHGSEL GG Storage Temperature Range ................. 65C to 150C + V 17 20 V CCP Lead Temperature (Soldering, 10 sec).................. 300C SW 18 19 GND G PACKAGE (209 mils) 36-LEAD PLASTIC SSOP T = 100C, = 95C/ W JMAX JA Consult factory for Military grade parts. DC ELECTRICAL CHARACTERISTICS V = 25V, V = 16V, V = 12V, T = 25C unless otherwise noted. (Note 2) DCIN BAT1 BAT2 A SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Power Supplies V DCIN Operating Range (Mode 1) DCIN Selected 6 28 V DCIN V Battery 1 Operating Range (Mode 5) Battery 1 Selected 6 28 V BAT1 V Battery 2 Operating Range (Mode 6) Battery 2 Selected 6 28 V BAT2 V Backup Operating Range (Mode 8) Backup Operation 6 28 V BKUP I DCIN Operating Current (Mode 1) DCIN Selected 175 500 A DCIN I Battery 1 Operating Current (Mode 5) Battery 1 Selected 150 500 A VBAT1 I Battery 2 Operating Current (Mode 6) Battery 2 Selected 150 500 A VBAT2 I Backup Operating Current (Mode 8) Backup Operation (V = 6V) 40 100 A VBKUP BKUP V V Regulator Output Voltage (Modes 1, 5, 6) DCIN, Battery 1 or Battery 2 Selected l 4.0 4.8 6.0 V CCP CCP V V Regulator Output Voltage (Modes 1, 5, 6) DCIN, Battery 1 or Battery 2 Selected l 3.3 3.6 3.9 V CC CC V V Gate Supply Voltage (Modes 1, 5, 6) DCIN, Battery 1 or Battery 2 Selected l 34.0 36.3 40.0 V GG GG V UV Lockout Threshold (Mode 9) No Power, V Falling from 12V 4.0 4.5 5.0 V UVLO BATX V UV Lockout Hysteresis (Mode 9) No Power, V Rising from 1V 0.2 0.5 1.0 V UVLOHYS BATX 2 U W U W U WW