LTC6802IG-2 LINER [Linear Technology], LTC6802IG-2 Datasheet
LTC6802IG-2
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LTC6802IG-2 Summary of contents
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FeaTures Measures Li-Ion Cells in Series (60V Max) n Stackable Architecture Enables Monitoring High n Voltage Battery Stacks Individually Addressable with 4-Bit Address n 0.25% Maximum Total Measurement Error n 13ms to Measure All Cells in a ...
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... LEAD FREE FINISH TAPE AND REEL LTC6802IG-2#PBF LTC6802IG-2#TRPBF 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: ...
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T SYMBOL PARAMETER DC Specifications V Measurement Resolution ACC ADC Offset Voltage ADC Gain Error V Total Measurement Error ERR V Cell Voltage Range CELL V Common Mode Voltage Range Measured CM ...
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LTC6802-2 elecTrical characTerisTics temperature range, otherwise specifications are at T SYMBOL PARAMETER Discharge Switch On-Resistance Temperature Range Thermal Shutdown Temperature Thermal Shutdown Hysteresis Timing Specifications t Measurement Cycle Time CYCLE t SDI Valid to SCKI Rising Setup 1 t SDI ...
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Typical perForMance characTerisTics Cell Measurement Total Unadjusted Error –40° 25° 85° 125° –2 –4 –6 –8 –10 0 0.5 1.0 1.5 2.0 ...
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LTC6802-2 Typical perForMance characTerisTics Cell Input Bias Current During Conversion 2.70 CELL INPUT = 3.6V 2.65 2.60 2.55 2.50 2.45 2.40 2.35 –40 – 100 120 TEMPERATURE (°C) 68022 G04 Internal Die Temperature Measurement vs ...
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Typical perForMance characTerisTics V Line Regulation REG 5.5 5.0 4 25°C A 4.0 3.5 NO EXTERNAL LOAD ON V (CONTINUOUS CELL CONVERSIONS) 3 SUPPLY VOLTAGE (V) Die Temperature Increase vs Discharge Current in Internal FET ...
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LTC6802-2 pin FuncTions + V (Pin 1): Tie Pin 1 to the most positive potential in + the battery stack. V must be approximately the same potential as C12. C12, C11, C10, C9, C8, C7, C6, C5, C4, C3, C2, ...
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FuncTions pin becomes high impedance. Either a “1” “0” is read back, depending on the voltage present at Pin 35. The GPIOs make it possible to turn on/off circuitry around the LTC6802-2, or read logic values from ...
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LTC6802-2 TiMing DiagraM t 1 SCKI D3 SDI CSBI D4 SDO PREVIOUS COMMAND operaTion THEORY OF OPERATION The LTC6802 data acquisition IC capable of mea- suring the voltage of 12 series connected battery cells. An input multiplexer connects ...
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LTC6802 CSBI C12 SDO + S12 SDI C11 SCKI + S11 A3 ADDRESS 1 C10 A2 + S10 GPIO2 C8 GPIO1 + S8 WDTB C7 MMB + S7 TOS C6 ...
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LTC6802-2 operaTion MUX – V Figure 2. Open Connection + MUX – V Figure 3. Open ...
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DISCHARGING DURING CELL MEASUREMENTS The primary cell voltage A/D measurement commands (STCVAD and STOWAD) automatically turn off a cell’s discharge switch while its voltage is being measured. The discharge switches for the cell above and the cell below will ...
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LTC6802-2 applicaTions inForMaTion USING THE LTC6802-2 WITH LESS THAN 12 CELLS The LTC6802-2 can typically be used with as few as 4 cells. The minimum number of cells is governed by the supply voltage requirements of the LTC6802-2. The sum ...
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MODES OF OPERATION The LTC6802-2 has three modes of operation: standby, measure and monitor. Standby mode is a power saving state where all circuits except the serial interface are turned off. In measure mode, the LTC6802-2 is used ...
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LTC6802-2 applicaTions inForMaTion Table 1. Monitor Mode Cell Selection WDTB GPIO2 GPIO1 CELL INPUTS MONITORED ...
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CSBI SCKI SDI MSB (CMD) SDO CSBI SCKI SDI MSB (CMD) SDO With broadcast commands all devices can be sent com- mands simultaneously. This is useful for A/D conversion and polling commands. It can also be used with ...
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LTC6802-2 applicaTions inForMaTion is enabled when the LVLPL bit is low. After entering a polling command, the data out line will be driven by the slave devices based on their status. When polling for the A/D converter status, data out ...
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Table 2. Protocol Key PEC Packet error code (CRC-8) N Number of bits … Continuation of protocol Table 3. Broadcast Poll Command 8 Command Poll Data Table 4. Broadcast Read 8 8 Command Data Byte Low … Table ...
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LTC6802-2 applicaTions inForMaTion Commands Table 9. Command Codes Write Configuration Register Group Read Configuration Register Group Read Cell Voltage Register Group Read Flag Register Group Read Temperature Register Group Start Cell Voltage A/D Conversions and Poll Status Start Open-Wire A/D ...
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Memory Map Table 10 through Table 15 show the memory map for the LTC6802-2. Table 15 gives bit descriptions. Table 10. Configuration (CFG) Register Group REGISTER RD/WR BIT 7 CFGR0 RD/WR WDT CFGR1 RD/WR DCC8 CFGR2 RD/WR MC4I ...
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LTC6802-2 applicaTions inForMaTion Table 12. Flag (FLG) Register Group REGISTER RD/WR BIT 7 FLGR0 RD C4OV FLGR1 RD C8OV FLGR2 RD C12OV* *Bits C11UV, C12UV, C11OV, and C12OV are always low if the CELL10 bit in register CFGR0 is high. ...
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Table 15. Memory Bit Descriptions NAME DESCRIPTION CDC Comparator Duty Cycle CELL10 10-Cell Mode LVLPL Level Polling Mode GPIO1 GPIO1 Pin Control GPIO2 GPIO2 Pin Control WDT Watchdog Timer DCCx Discharge Cell x VUV Undervoltage Comparison Voltage* VOV ...
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LTC6802-2 applicaTions inForMaTion SERIAL COMMAND Example for LTC6802-2 (Addressable Configuration) Examples below use a configuration of three stacked devices: bottom (B), middle (M), and top (T) Write Configuration Registers (Broadcast Command) 1. Pull CSBI low 2. Send WRCFG command byte ...
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Poll Interrupt Status (Level Polling) 1. Pull CSBI low 2. Send Address byte for bottom device 3. Send PLINT command byte 4. SDO output from bottom device pulled low if any device has an interrupt condition; otherwise, SDO ...
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LTC6802-2 applicaTions inForMaTion Internal Protection Diodes Each pin of the LTC6802-2 has protection diodes to help prevent damage to the internal device structures caused by external application of voltages beyond the supply rails as shown in Figure 9. The diodes ...
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No resistor should be placed in series with the V Because the supply current flows from the V resistance on this pin could generate a significant conver- sion error for CELL1. READING EXTERNAL TEMPERATURE PROBES Using Dedicated Inputs ...
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LTC6802-2 applicaTions inForMaTion LTC6802-2 V REG 200k V REF V TEMP2 V TEMP1 NC − V Figure 14. Using Diode Sensors as Hot-Spot Detectors ADDING CALIBRATION AND FULL-STACK MEASUREMENTS By adding multiplexing hardware, additional signals can be digitized by the ...
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PROVIDING HIGH SPEED OPTO-ISOLATION OF THE SPI DATA PORT Isolation techniques that are capable of supporting the 1Mbps data rate of the LTC6802-2 require more power on the isolated (battery) side than can be furnished by the V ...
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LTC6802-2 applicaTions inForMaTion ADVANTAGES OF DELTA-SIGMA ADCS The LTC6802-2 employs a delta-sigma analog-to-digital converter for voltage measurement. The architecture of delta-sigma converters can vary considerably, but the common characteristic is that the input is sampled many times over the course ...
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Converter Details The LTC6802-2’s ADC has a second-order delta-sigma modulator followed by a Sinc2, finite impulse response (FIR) digital filter. The front-end sample rate is 512ksps, which greatly reduces input filtering requirements. A simple 16kHz, 1-pole filter composed ...
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LTC6802-2 package DescripTion 7.8 – 8.2 0.25 ±0.05 RECOMMENDED SOLDER PAD LAYOUT APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED 5.00 – 5.60* (.197 – .221) PARTING LINE 0.10 – 0.25 0.55 – 0.95** (.004 – .010) (.022 – ...
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REV DATE DESCRIPTION A 01/10 Additions to Absolute Maximum Ratings Changes to Electrical Characteristics Change to Graph G10 Text Changes to Pin Functions Replaced Open-Connection Detection Section Edits to Figures 1, 9 Text Changes to Operation Section Text ...
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LTC6802-2 Typical applicaTion LTC6802 LTC6802 LTC6802 relaTeD parTs PART NUMBER DESCRIPTION LTC6802-1 Multicell Battery Stack Monitor with Daisy Chained Serial Interface Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: ...