DC2703A-A-KIT Analog Devices

LT8491 High Voltage Buck-Boost Battery Charge Controller with Maximum Power Point 2 Tracking (MPPT) and I C FEATURES DESCRIPTION n V Range: 6V to 80V The LT 8491 is a buck-boost switching regulator battery IN n V Range: 1.3V to 80V charger that implements a constant-current constant- BAT n Single Inductor Allows V Above, Below, or Equal voltage (CCCV) charging profile used for most battery IN to V types, including sealed lead-acid (SLA), flooded, gel and BAT n Automatic MPPT for Solar Powered Charging lithium-ion. n Automatic Temperature Compensation The device operates from input voltages above, below or 2 n I C Telemetry and Configuration equal to the output voltage and can be powered by a solar n Internal EEPROM for Configuration Storage panel or a DC power supply. On-chip logic provides auto- n Operation from Solar Panel or DC Supply matic maximum power point tracking (MPPT) for solar n Four Integrated Feedback Loops powered applications. The LT8491 can perform automatic n Synchronizable Fixed Frequency: 100kHz to 400kHz temperature compensation by sensing an external therm- n 64-Lead (7mm 11mm 0.75mm) QFN Package istor thermally coupled to the battery. The STATUS pin can be used to drive an LED indicator lamp. The device is APPLICATIONS available in a low profile (0.75mm) 7mm 11mm 64-lead QFN package. n Solar Powered Battery Chargers All registered trademarks and trademarks are the property of their respective owners. n Multiple Types of Lead-Acid Battery Charging n Li-Ion Battery Charger n Battery Equipped Industrial or Portable Military Equipment TYPICAL APPLICATION Simplified Solar Powered Battery Charger Schematic Maximum Power GATEV GATEV CC CC Point Tracking SOLAR PANEL FULL PANEL SCAN LOAD V PANEL TG1 BOOST1 SW1 BG1 CSP CSN BG2 SW2 BOOST2 TG2 V BAT 6V/DIV CSNIN CSPOUT PERTURB CSPIN CSNOUT + PERTURB AND AND V IN OBSERVE EXTV CC OBSERVE RECHARGABLE 2 I C INTERFACE IMON IN LT8491 BATTERY SDA TELEMETRY 0.2V/DIV AV DD STATUS CONTROL SCL 8491 TA01b CONFIGURATION 0.5s/DIV GATEV GATEV THERMISTOR CC CC TEMPSENSE INTV CC STATUS CA GND AV AV DD DD 8491 TA01a Rev. 0 1 Document Feedback For more information www.analog.comLT8491 TABLE OF CONTENTS 2 Features ..................................................... 1 I C Register Map .......................................... 27 2 Applications ................................................ 1 I C Register Descriptions ................................ 30 Typical Application ........................................ 1 Telemetry Registers ................................................30 TELE TBAT ................................................................. 30 Description.................................................. 1 TELE POUT .................................................................31 Absolute Maximum Ratings .............................. 4 TELE PIN .....................................................................31 Order Information .......................................... 4 TELE EFF .....................................................................31 Pin Configuration .......................................... 4 TELE IOUT ................................................................. 32 Electrical Characteristics ................................. 5 TELE IIN ..................................................................... 32 Typical Performance Characteristics ................... 8 TELE VBAT ................................................................. 32 Pin Functions .............................................. 10 TELE VIN .................................................................... 33 Block Diagram ............................................. 13 TELE VINR ................................................................. 33 Operation................................................... 14 Status Registers .....................................................34 Overview ................................................................. 14 STAT CHARGER ......................................................... 34 2 I C Serial Interface.................................................. 14 2 STAT SYSTEM ........................................................... 35 I C: START and STOP Conditions ...............................14 STAT SUPPLY ............................................................ 36 2 I C: ACKnowledge .......................................................14 2 STAT TSx REMAIN ................................................... 36 I C: Chip Addressing ...................................................15 STAT CHRG FAULTS ................................................ 37 2 I C: Clock Stretching ...................................................15 2 STAT VERSION .......................................................... 38 I C: Data Transfer Transactions ..................................15 STAT BOOT CRC ....................................................... 38 2 I C: Powering the Interface .........................................15 2 STAT CFG CRC.......................................................... 38 I C Data .................................................................. 16 Control The EEPROM ..............................................39 Data: Memory Regions ...............................................16 CTRL WRT TO BOOT .............................................. 39 Data: Bytes, Words and Long Words .........................17 CTRL EE WRT EN ................................................... 39 Data: Min/Max Register Values ..................................17 Control Other Functions ..........................................40 Data: Access Permissions...........................................17 CTRL HALT STARTUP ............................................. 40 Startup Sequence ................................................... 18 CTRL CHRG EN ........................................................ 40 Battery Charging Algorithm ....................................20 CTRL RESTART CHIP ...............................................41 Stage0: Trickle Charging ........................................... 20 CTRL RESET FLAG ...................................................41 Stage1: Full Constant Current ................................... 20 CTRL UPDATE TELEM ..............................................41 Stage2: Constant Voltage .......................................... 21 Configure The Telemetry .........................................42 Stage3: (Optional) Reduced Constant Voltage ......... 21 CFG RSENSE1 ........................................................... 42 Done Charging ............................................................ 21 CFG RIMON OUT ..................................................... 43 Charging Faults ........................................................... 21 CFG RSENSE2 ........................................................... 43 Maximum Power Point Tracking .............................23 CFG RDACO ............................................................... 43 Telemetry Operation ...............................................23 CFG RFBOUT1 ........................................................... 44 Telemetry: Configuration Settings ..............................24 CFG RFBOUT2 ........................................................... 44 Telemetry: Acquisition .................................................24 CFG RDACI ................................................................ 44 CRC Operation ........................................................ 24 CFG RFBIN2 ............................................................... 45 EEPROM Operation .................................................25 CFG RFBIN1 ............................................................... 45 EEPROM: Startup ....................................................... 25 Configure Initial Charger Enable .............................45 EEPROM: Reading ...................................................... 25 CFG INIT CHRG EN ................................................. 45 EEPROM: Writing ....................................................... 25 Rev. 0 2 For more information www.analog.com