LTC6802IG-1 Linear Technology Corporation, LTC6802IG-1 Datasheet
LTC6802IG-1
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LTC6802IG-1 Summary of contents
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... Each cell input has an associated MOSFET switch for discharging overcharged cells. The related LTC6802-2 offers an individually addressable serial interface. L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. SERIAL DATA LTC6802-1 ...
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... For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: 2 PIN CONFIGURATION + + – – 1. 0.7V PART MARKING PACKAGE DESCRIPTION LTC6802IG-1 44-Lead Plastic SSOP http://www.linear.com/leadfree/ http://www.linear.com/tapeandreel/ TOP VIEW 1 CSBI CSBO 44 2 SDO SDOI 43 3 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER DC Specifi cations 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 ...
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LTC6802-1 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Discharge Switch On-Resistance Temperature Range Thermal Shutdown Temperature Thermal Shutdown Hysteresis Voltage Mode Timing Specifi cations t Measurement Cycle Time CYCLE t SDI Valid to SCKI Rising ...
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PIN FUNCTIONS CSBO (Pin 1): Chip Select Output (Active Low). CSBO is a buffered version of the chip select input, CSBI. CSBO drives the next IC in the daisy chain. See Serial Port in the Applications Information section. SDOI (Pin ...
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LTC6802-1 PIN FUNCTIONS GPIO1, GPIO2 (Pins 38, 39): General Purpose Input/Out- put. The operation of these pins depends on the state of the MMB pin. When MMB is high, the pins behave as traditional GPIOs. By writing a “0” to ...
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BLOCK DIAGRAM 5 C12 10k 6 S12 7 C11 10k 10k 10k – V 10Ω 30 DIE NC TEMP Δ∑ A/D CONVERTER MUX REFERENCE EXTERNAL TEMP ...
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LTC6802-1 TIMING DIAGRAM SCKI D3 SDI CSBI D4 D3 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 ...
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OPERATION BATTERY POSITIVE 350V LTC6802 CSBO CSBI SDOI SDO SCKO SDI + V SCKI C12 V MODE S12 GPIO2 C11 GPIO1 S11 WDTB C10 MMB S10 TOS C9 V REG S9 V REF C8 V TEMP2 S8 V ...
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LTC6802-1 OPERATION MUX C2 C1 – V Figure 2. Open Connection a zero reading because the ADC input resistance is too large to discharge the capacitors on the input pin. Consider the example in Figure 3 ...
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OPERATION identical codes. For Self Test 1 the registers will contain 0x555. For Self Test 2, the registers will contain 0xAAA. The time required for the self test function is the same as required to measure all cell voltages or ...
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LTC6802-1 APPLICATIONS INFORMATION NEXT HIGHER GROUP OF 7 CELLS V C12 S12 C11 S11 C10 S10 NEXT LOWER GROUP OF 7 ...
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APPLICATIONS INFORMATION MODES OF OPERATION The LTC6802-1 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 LTC6802-1 is used ...
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LTC6802-1 APPLICATIONS INFORMATION BATTERY POSITIVE LTC6802-1 CSBI CSBO SDO SDOI SDI SCKO + SCKI V V C12 MODE GPIO2 S12 GPIO1 C11 WDTB S11 MMB C10 TOS S10 V C9 REG V S9 REF V C8 TEMP2 V S8 TEMP1 ...
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APPLICATIONS INFORMATION Table 1. Monitor Mode Cell Selection WDTB GPIO2 GPIO1 CELL INPUTS MONITORED MMB ...
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LTC6802-1 APPLICATIONS INFORMATION The voltage mode pin (V ) determines whether the low MODE side serial port is confi gured as voltage mode or current mode. For the bottom device in a daisy-chain stack, this pin must be pulled high ...
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APPLICATIONS INFORMATION CSBI SCKI SDI MSB (CMD) SDO Network Layer Broadcast Commands: A broadcast command is one to which all devices on the bus will respond, regardless of device address. See the Bus Protocols and Commands sections. In daisy chained ...
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LTC6802-1 APPLICATIONS INFORMATION out will be low when any device is busy performing an A/D conversion and will be high when no device is busy. Similarly, when polling for interrupt status, the output will be low when any device has ...
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APPLICATIONS INFORMATION Commands Table 6. Command Codes Write Confi guration Register Group Read Confi guration 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 ...
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LTC6802-1 APPLICATIONS INFORMATION Memory Map Table 7 through Table 12 show the memory map for the LTC6802-1. Table 12 gives bit descriptions. Table 7. Confi guration (CFG) Register Group REGISTER RD/WR BIT 7 CFGR0 RD/WR WDTEN CFGR1 RD/WR DCC8 CFGR2 ...
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APPLICATIONS INFORMATION Table 9. 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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LTC6802-1 APPLICATIONS INFORMATION Table 12. 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 WDTEN Watchdog Timer Enable DCCx Discharge Cell x VUV Undervoltage Comparison ...
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APPLICATIONS INFORMATION SERIAL COMMAND EXAMPLES LTC6802-1 (Daisy Chained Confi guration) Examples below use a confi guration of three stacked devices: bottom (B), middle (M), and top (T) Write Confi guration Registers 1. Pull CSBI low 2. Send WRCFG command byte ...
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LTC6802-1 APPLICATIONS INFORMATION Poll Interrupt Status (Level Polling) 1. Pull CSBI low 2. Send PLINT command byte 3. SDO output from bottom device pulled low if any device has an interrupt condition; otherwise, SDO high 4. Pull CSBI high to ...
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APPLICATIONS INFORMATION Battery Interconnection Integrity The FMEA scenarios involving a break in the stack of battery cells are potentially the most damaging. In the case where the battery stack has a discontinuity between groupings of cells monitored by LTC6802-1 ICs, ...
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LTC6802-1 APPLICATIONS INFORMATION 500kHz may be benefi cial. Since the delta-sigma integra- tion bandwidth is about 1kHz, the fi lter corner need not be lower than this to assure accurate conversions. Series resistors of 100Ω may be inserted in the ...
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APPLICATIONS INFORMATION Figure 16. Using both GPIO pins eight sensor inputs can be supported. Another method of multiple sensor support is possible without the use of any GPIO pins. If the sensors are PN diodes and several used ...
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LTC6802-1 APPLICATIONS INFORMATION CELL12 GPIO2 GPIO1 WDTB V REG LTC6802-1 TP0610K TP0610K CELL1 100Ω Figure 18. Providing Measurement of Calibration Reference and Full-Stack Voltage Through CELL1 Port 3.57k 3.57k CSBI SDO SDI SCKI V REG 100nF 249Ω LTC6802-1 ISOLATED V ...
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APPLICATIONS INFORMATION logic voltage (~4V) to the opto-coupler isolated side, from energy provided by host-furnished 5V. This circuit provides totally galvanic isolation between the batteries and the host processor, with an insulation rating of 560V continuous, 2500V transient. PCB LAYOUT ...
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LTC6802-1 APPLICATIONS INFORMATION Converter Details The LTC6802-1’s ADC has a second order delta sigma modulator followed by a Sinc2, fi nite impulse response (FIR) digital fi lter. The front-end sample rate is 512ksps, which greatly reduces input fi ltering requirements. ...
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... ONE ANOTHER WITHIN 0.08mm AT SEATING PLANE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... Multicell Battery Stack Monitor with Parallel Addressed Serial Interface Linear Technology Corporation 32 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● COMMENTS Functionality equivalent to LTC6802-1, Allows for Individually Addressable Battery Stack Topologies www.linear.com ● 68021p LT 0808 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2008 ...