LTC6813-1 Multicell Battery Monitor - analog.com

1 LTC6813-11 Rev. BFor more information FeedbackTYPICAL APPLICATION FEATURESDESCRIPTION18-Cell Battery Stack Monitor with Daisy Chain Interface The LT C 6813-1 is a Multicell Battery stack Monitor that measures up to 18 series connected Battery cells with a total measurement error of less than The cell measurement range of 0V to 5V makes the LTC6813-1 suitable for most Battery chemistries. All 18 cells can be measured in 290 s, and lower data acquisition rates can be selected for high noise LTC6813-1 devices can be connected in series, permitting simultaneous cell monitoring of long, high voltage Battery strings. Each LTC6813-1 has an isoSPI interface for high speed, RF immune, long distance com-munications. Multiple devices are connected in a daisy chain with one host processor connection for all devices.

2 This daisy chain can be operated bidirectionally, ensuring communication integrity, even in the event of a fault along the communication LTC6813-1 can be powered directly from the bat-tery stack or from an isolated supply. The LTC6813-1 includes passive balancing for each cell, with individual PWM duty cycle control for each cell. Other features include an onboard 5V regulator, nine general purpose I/O lines and a sleep mode, where current consumption is reduced to 6 18 Measurement Error vs TemperatureAPPLICATIONS nMeasures Up to 18 Battery Cells in Series Maximum Total Measurement Error nStackable Architecture for High Voltage Systems nBuilt-In isoSPI Interface n1Mb Isolated Serial Communications nUses a Single Twisted Pair, Up to 100 Meters nLow EMI Susceptibility and Emissions nBidirectional for Broken Wire Protection n290 s to Measure All Cells in a System nSynchronized Voltage and Current Measurement n16-Bit Delta-Sigma ADC with Programmable Noise Filter nEngineered for ISO 26262-Compliant Systems nPassive Cell Balancing Up to 200mA (Max)

3 With Programmable Pulse-Width Modulation n9 General Purpose Digital I/O or analog Inputs nTemperature or Other Sensor Inputs nConfigurable as an I2C or SPI Master n6 A Sleep Mode Supply Current n64-Lead eLQFP Package nAEC-Q100 Qualified for Automotive Applications nElectric and Hybrid Electric Vehicles nBackup Battery Systems nGrid Energy Storage nHigh Power Portable EquipmentAll registered trademarks and trademarks are the property of their respective owners. Protected by patents, including 8908779, 9182428, 9270133.++68131 TA01aLTC6813-1 ISOLATED DATA WITHWIRE BREAK PROTECTION++ CELL 18 CELL 17 CELL 2 CELL 118-Cell Monitor and Balance ICCELL VOLTAGE = TYPICAL UNITSTEMPERATURE ( C) 50 250255075100125 ERROR (mV)68131 TA01bLTC6813-12 Rev. BFor more information OF CONTENTS Features.

4 1 Applications ..1 Typical Application .. 1 Absolute Maximum Ratings ..3 Order Information ..3 Pin Configuration ..3 Electrical Characteristics ..4 Typical Performance Characteristics ..9 Pin Functions ..15 Block Diagram ..16 Improvements from the LTC6811-1 .. 18 State Diagram ..18 Core LTC6813-1 State Descriptions ..18isoSPI State Descriptions ..19 Power Consumption ..19 ADC Operation ..20 Data Acquisition System Diagnostics ..26 Watchdog and Discharge Timer ..33 Reset Behaviors ..35S Pin Pulse-Width Modulation for Cell Balancing . 36 Discharge Timer Monitor ..36I2C/SPI Master on LTC6813-1 Using GPIOs ..37S Pin Pulsing Using the S Pin Control Settings ..42S Pin Muting ..43 Serial Interface Overview ..434-Wire Serial Peripheral Interface (SPI) Physical Layer ..432-Wire Isolated Interface (isoSPI) Physical Layer.

5 43 Data Link Layer ..54 Network Layer ..54 Applications Information ..70 Providing DC Power ..70 Internal Protection and Filtering ..71 Cell Balancing ..74 Discharge Control During Cell Measurements ..75 Digital Applications ..85 Reading External Temperature Probes ..87 Package Description ..88 Revision History ..89 Typical Application ..90 Related Parts ..90 LTC6813-13 Rev. BFor more information CONFIGURATIONABSOLUTE MAXIMUM RATINGST otal Supply Voltage V+ to V .. VSupply Voltage (Relative to C12) V+ to C12 ..50 VInput Voltage (Relative to V ) C0 .. to 6V C18 .. to MIN (V+ + , V) C(n), S(n) .. to MIN (8 n, V) IPA, IMA, IPB, IMB .. to VREG + , 6V DRIVE .. to 7V All Other Pins .. to 6 VVoltage Between Inputs C(n) to C(n 1), S(n) to C(n 1).

6 To 8V C18 to C15, C15 to C12, C12 to C9, C9 to C6, C6 to C3, C3 to C0 .. to 21 VCurrent In/Out of Pins All Pins Except VREG, IPA, IMA, IPB, IMB, C(n), S(n) ..10mA IPA, IMA, IPB, IMB ..30mASpecified Junction Temperature Range LTC6813I-1 .. 40 C to 85 C LTC6813H -1 .. 40 C to 125 CJunction Temperature ..150 CStorage Temperature Range .. 65 C to 150 CDevice HBM ESD Classification Level 1 CDevice CDM ESD Classification Level C5(Note 1)12345678910111213141516484746454443424 14039383736353433V+C18S18C17S17C16S16C15 S15C14S14C13S13C12S12C111718192021222324 2526272829303132S11C10S10C9S9C8S8C7S7C6S 6C5S5C4S4C364636261605958575655545352515 049 IPBIMBSCK (IPA)*CSB (IMA)*V V **ICMPIBIASWDTISOMDSDO (NC)*SDI (NC)*DTENVREF1 VREF2 DRIVEVREGGPIO9 GPIO8 GPIO7 GPIO6 GPIO5 GPIO4 GPIO3 GPIO2 GPIO1C0S1C1S2C2S3 TOP VIEWLWE PACKAGE64-LEAD (10mm 10mm) PLASTIC eLQFPTJMAX = 150 C, JA = 17 C/W, JC = C/WEXPOSED PAD (PIN 65) IS V , MUST BE SOLDERED TO PCB65V *The Function of These Pins Depends on the Connection of ISOMD: ISOMD Tied to V : CSB, SCK, SDI, SDO ISOMD Tied to VREG.

7 IPA, IMA, NC, NC**This Pin Must Be Connected to V ORDER INFORMATIONAUTOMOTIVE PRODUCTS**TRAY (160PC)TAPE AND REEL (1500PC)PART MARKING*PACKAGE DESCRIPTIONMSL RATINGSPECIFIED JUNCTION TEMPERATURE RANGELTC6813 ILWE-1#3 ZZPBFLTC6813 ILWE-1#3 ZZTRPBFLTC6813 LWE-164-Lead Plastic eLQFP3 40 C to 85 CLTC6813 HLWE-1#3 ZZPBFLTC6813 HLWE-1#3 ZZTRPBFLTC6813 LWE-164-Lead Plastic eLQFP3 40 C to 125 CContact the factory for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping and reel specifications. Some packages are available in 500 unit reels through designated sales channels with #TRMPBF suffix.**Versions of this part are available with controlled manufacturing to support the quality and reliability requirements of automotive applications.

8 These models are designated with a #3ZZ suffix. Only the automotive grade products shown are available for use in automotive applications. Contact your local analog Devices account representative for specific product ordering information and to obtain the specific Automotive Reliability reports for these BFor more information CHARACTERISTICS The l denotes the specifications which apply over the full specified temperature range, otherwise specifications are at TA = 25 C. The test conditions are V+ = , VREG = unless otherwise noted. The ISOMD pin is tied to the V pin, unless otherwise DC SpecificationsMeasurement Offset Voltage(Note 2) Gain Error(Note 2) Measurement Error (TME) in Normal ModeC(n) to C(n 1), GPIO(n) to V = 0 (n) to C(n 1) = (n) to C(n 1), GPIO(n) to V = , LTC6813Il (n) to C(n 1), GPIO(n) to V = , LTC6813Hl (n) to C(n 1) = (n) to C(n 1), GPIO(n) to V = , LTC6813Il (n) to C(n 1), GPIO(n) to V = , LTC6813Hl (n) to C(n 1) = (n) to C(n 1), GPIO(n) to V = , LTC6813Il (n) to C(n 1), GPIO(n) to V = , LTC6813Hl (n) to C(n 1), GPIO(n) to V = 1mVSum of All Cells l Temperature, T = Maximum Specified Temperature 5 CVREG Pinl 1 Pinl Supply Voltage, VREGDl Measurement Error (TME) in Filtered ModeC(n) to C(n 1), GPIO(n) to V = 0 (n) to C(n 1) = (n)

9 To C(n 1), GPIO(n) to V = , LTC6813Il (n) to C(n 1), GPIO(n) to V = , LTC6813Hl (n) to C(n 1) = (n) to C(n 1), GPIO(n) to V = , LTC6813Il (n) to C(n 1), GPIO(n) to V = , LTC6813Hl (n) to C(n 1) = (n) to C(n 1), GPIO(n) to V = , LTC6813Il (n) to C(n 1), GPIO(n) to V = , LTC6813Hl (n) to C(n 1), GPIO(n) to V = 1mVSum of All Cells l Temperature, T = Maximum Specified Temperature 5 CVREG Pinl 1 Pinl Supply Voltage, VREGDl BFor more information Measurement Error (TME) in Fast ModeC(n) to C(n 1), GPIO(n) to V = 0 2mVC(n) to C(n 1), GPIO(n) to V = 4mVC(n) to C(n 1), GPIO(n) to V = 6mVC(n) to C(n 1), GPIO(n) to V = (n) to C(n 1), GPIO(n) to V = 10mVSum of All Cells l Temperature, T = Maximum Specified Temperature 5 CVREG Pinl Pinl Supply Voltage, VREGDl RangeC(n) n = 1 to 18lC(n 1)C(n 1) + 5VC0 l01 VGPIO(n) n = 1 to 9l05 VILI nput Leakage Current When Inputs Are Not Being MeasuredC(n) n = 0 to 18l10 250nAGPIO(n) n = 1 to 9l10 250nAInput Current When Inputs Are Being Measured (State.)

10 Core = MEASURE)C(n) n = 0 to 18 1 AGPIO(n) n = 1 to 9 1 AInput Current During Open Wire Detectionl70100130 AVoltage Reference SpecificationsVREF11st Reference VoltageVREF1 Pin, No V1st Reference Voltage TCVREF1 Pin, No Load3ppm/ C1st Reference Voltage Thermal HysteresisVREF1 Pin, No Load20ppm1st Reference Voltage Long Term DriftVREF1 Pin, No Load20ppm/ khrVREF22nd Reference VoltageVREF2 Pin, No Pin, 5k Load to V Reference Voltage TCVREF2 Pin, No Load10ppm/ C2nd Reference Voltage Thermal HysteresisVREF2 Pin, No Load100ppm2nd Reference Voltage Long Term DriftVREF2 Pin, No Load60ppm/ khrGeneral DC SpecificationsIVPV+ Supply Current (See Figure 1: LTC6813-1 Operation State Diagram)State: Core = SLEEP, isoSPI = IDLE VREG = A VREG = A VREG = 5V35 A VREG = 5Vl39 AState: Core = STANDBY l9 614 1422 28 A AState: Core = REFUP mAState: Core = MEASURE mAELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full specified temperature range, otherwise specifications are at TA = 25 C.