LTC6802-1_1

LTC6802-1 Multicell Battery Stack Monitor FEATURES n n n n n DESCRIPTION The LTC®6802-1 is a complete battery monitoring IC that includes a 12-bit ADC, a precision voltage reference, a high voltage input multiplexer and a serial interface. Each LTC6802-1 can measure up to 12 series connected battery cells with an input common mode voltage up to 60V. In addition, multiple LTC6802-1 devices can be placed in series to monitor the voltage of each cell in a long battery string. The unique level-shifting serial interface allows the serial ports of these devices to be daisy-chained without optocouplers or isolators. When multiple LTC6802-1 devices are connected in series they can operate simultaneously, permitting all cell voltages in the stack to be measured within 13ms. To minimize power, the LTC6802-1 offers a measure mode, which simply monitors each cell for overvoltage and undervoltage conditions. A standby mode is also provided. Each cell input has an associated MOSFET switch for discharging overcharged cells. For large battery stack applications requiring individually addressable serial communications, see the LTC6802-2. n n n n n n n Measures up to 12 Li-Ion Cells in Series (60V Max) Stackable Architecture Enables >1000V Systems 0.25% Maximum Total Measurement Error 13ms to Measure All Cells in a System Cell Balancing: On-Chip Passive Cell Balancing Switches Provision for Off-Chip Passive Balancing Two Thermistor Inputs Plus On-Board Temperature Sensor 1MHz Daisy-Chainable Serial Interface High EMI Immunity Delta Sigma Converter with Built-In Noise Filter Open Wire Connection Fault Detection Low Power Modes 44-Lead SSOP Package APPLICATIONS n n n n Electric and Hybrid Electric Vehicles High Power Portable Equipment Backup Battery Systems High Voltage Data Acquisition Systems L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATION NEXT 12-CELL PACK ABOVE V + LTC6802-1 SERIAL DATA TO LTC6802-1 ABOVE DIE TEMP REGISTERS AND CONTROL Measurement Error Over Extended Temperature 0.30 0.25 MEASUREMENT ERROR (%) 0.20 0.15 0.10 0.05 0 –0.05 –0.10 –0.15 –0.20 –0.25 7 REPRESENTATIVE UNITS 12-CELL BATTERY STRING MUX 12-BIT Δ∑ ADC V– NEXT 12-CELL PACK BELOW EXTERNAL TEMP VOLTAGE REFERENCE 68021 TA01a SERIAL DATA TO LTC6802-1 BELOW –0.30 –50 –25 0 25 50 75 TEMPERATURE (°C) 100 125 68021 TA01b 100k 100k NTC 68021fa 1 LTC6802-1 ABSOLUTE MAXIMUM RATINGS (Note 1) PIN CONFIGURATION TOP VIEW CSBO SDOI SCKO V+ C12 S12 C11 S11 C10 1 2 3 4 5 6 7 8 9 44 CSBI 43 SDO 42 SDI 41 SCKI 40 VMODE 39 GPIO2 38 GPIO1 37 WDTB 36 MMB 35 TOS 34 VREG 33 VREF 32 VTEMP2 31 VTEMP1 30 NC 29 V– 28 S1 27 C1 26 S2 25 C2 24 S3 23 C3 Total Supply Voltage (V+ to V–) .................................60V Input Voltage (Relative to V–) C1 ............................................................ –0.3V to 9V C12 .......................................... V+ – 0.6V to V+ + 0.3V Cn (Note 5) ......................... –0.3V to min (9 • n, 60V) Sn (Note 5) ......................... –0.3V to min (9 • n, 60V) CSBO, SCKO, SDOI .................. V+ – 0.6V to V+ + 0.3V All other pins ........................................... –0.3V to 7V Voltage Between Inputs Cn to Cn-1 ................................................ –0.3V to 9V Sn to Cn-1 ................................................ –0.3V to 9V C12 to C8 ............................................... –0.3V to 25V C8 to C4 ................................................. –0.3V to 25V C4 to V– ................................................. –0.3V to 25V Operating Temperature Range .................–40°C to 85°C Specified Temperature Range ..................–40°C to 85°C Junction Temperature ........................................... 150°C Storage Temperature Range .................. –65°C to 150°C *n = 1 to 12 S10 10 C9 11 S9 12 C8 13 S8 14 C7 15 S7 16 C6 17 S6 18 C5 19 S5 20 C4 21 S4 22 G PACKAGE 44-LEAD PLASTIC SSOP TJMAX = 150°C, θJA = 70°C/W ORDER INFORMATION LEAD FREE FINISH LTC6802IG-1#PBF TAPE AND REEL LTC6802IG-1#TRPBF PART MARKING LTC6802G-1 PACKAGE DESCRIPTION 44-Lead Plastic SSOP TEMPERATURE RANGE –40°C to 85°C Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/ 68021fa 2 LTC6802-1 ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER DC Specifications VACC Measurement Resolution ADC Offset Voltage ADC Gain Error VERR Total Measurement Error Quantization of the ADC (Note 2) (Note 2) (Note 4) VCELL = 0V VCELL = 2.3V VCELL = 2.3V VCELL = 3.6V VCELL = 3.6V VCELL = 4.2V VCELL = 4.2V VCELL = 4.6V VTEMP = 2.3V VTEMP = 3.6V VTEMP = 4.2V Full Scale Voltage Range Range of Inputs CN for