BQ2040SN-C408 BENCHMARQ, BQ2040SN-C408 Datasheet
BQ2040SN-C408
Specifications of BQ2040SN-C408
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BQ2040SN-C408 Summary of contents
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Gas Gauge IC With SMBus Interface Features Provides accurate measurement of available charge in NiCd, NiMH, and Li-Ion batteries Supports SBS v1.0 data set and two-wire interface Monitors charge FET in Li-Ion pack protection circuit Designed for battery pack inte- ...
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Pin Descriptions Supply voltage input V CC ESCL Serial memory clock Output used to clock the data transfer be- tween the bq2040 and the external non- volatile configuration memory. ESDA Serial memory data and address Bidirectional pin used to ...
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Functional Description General Operation The bq2040 determines battery capacity by monitoring the amount of charge put into or removed from a re- chargeable battery. The bq2040 measures discharge and charge currents, estimates self-discharge, and monitors the battery for low-battery voltage ...
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Table 1. Configuration Memory Map Parameter Name Address EEPROM length 0x00 EEPROM check1 0x01 Remaining time alarm 0x02/0x03 Sets RemainingTimeAlarm (0x02) Remaining capacity alarm 0x04/0x05 Sets RemainingCapacityAlarm (0x01) Reserved 0x06/0x07 Reserved for future use Initial charging current 0x08/0x09 Sets ...
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Table 1. Configuration Memory Map (Continued) Parameter Name Address Charge efficiency 0x4b Full charge percentage 0x4c Digitial filter 0x4d Current integration gain 0x4e Self-discharge rate 0x4f Manufacturer data 0x50-0x55 Programs ManufacturerData (0x23) Voltage gain1 0x56/0x57 Battery divider calibration value Reserved ...
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Voltage Thresholds In conjunction with monitoring V SR currents, the bq2040 monitors the battery potential through the SB pin. The voltage potential is deter- mined through a resistor-divider network per the fol- lowing equation: R MBV 5 R 2.25 ...
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Inputs Main Counters and Capacity Reference (FCC) Outputs ing subsequent discharges, FCC is updated with the latest measured capacity in the Discharge Count Reg- ister plus the battery low amount, representing a dis- charge from full to below EDV1. charge ...
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Charge Counting Charge activity is detected based on a positive voltage on the SR input. If charge activity is detected, the bq2040 increments rate proportional to V and, if enabled, activates an LED display. Charge ac- ...
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Charge Suspension The bq2040 may temporarily suspend charge if it detects a charging fault. The charging faults include the follow- ing conditions: n Maximum Overcharge: If charging continues for more than the programmed maximum overcharge limit as defined in EE ...
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Table 3. bq2040 Current-Sensing Errors Symbol Parameter V Offset referred Integrated non-linearity INL error Integrated non- INR repeatability error Error Summary Capacity Inaccurate The FCC is susceptible to error on initialization updates ...
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Battery Address Command Code 0001011 Battery Address Command Code 0001011 8 1 Data byte low A Data byte high Battery Address S ...
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Table 4. bq2040 Register Functions Function ManufacturerAccess RemaningCapacityAlarm RemainingTimeAlarm BatteryMode AtRate AtRateTimeToFull AtRateTimeToEmpty AtRateOK Temperature Voltage Current AverageCurrent MaxError RelativeStateOfCharge AbsoluteStateOfCharge RemainingCapacity FullChargeCapacity RunTimeToEmpty AverageTimeToEmpty AverageTimeToFull ChargingCurrent ChargingVoltage Battery Status CycleCount DesignCapacity DesignVoltage SpecificationInfo ManufactureDate SerialNumber Reserved ManufacturerName DeviceName ...
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Table 4. bq2040 Register Functions (Continued) Function DeviceChemistry ManufacturerData FLAG1 and FLAG2 End of Discharge Voltage 1 (EDV1) End of Discharge Voltage Final (EDVF) Note: 1. Defaults after reset or power-up. Code Access 0x22 read 0x23 read 0x2f read 0x3e ...
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When the AtRate value is positive, the n AtRateTimeToFull function returns the predicted time to full-charge at the AtRate value of charge. When the AtRate value is negative, the n AtRateTimeToEmpty function returns the predicted operating time at the ...
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Accuracy the DesignCapacity after cali- bration MaxError() (0x0c) Returns the expected margin of error (%) in the state of charge calculation. Output: unsigned integer. Returns the percent un- certainty for selected information. Units: % Range 100% ...
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Output: unsigned integer. Returns the minutes of operation left. Units: minutes Range 65,534min Granularity: 2min or better Invalid data indication: 65,535 indicates battery is not being discharged. AverageTimeToFull() (0x13) This read-only word returns the predicted time until ...
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... This read-only string returns a character string where the first byte is the number of characters available. The maxi- mum number of characters is 11. The character string con- tains the battery manufacturer's name. For example, “Benchmarq” identifies the battery pack manufacturer as Benchmarq. Output: string or ASCII character string DeviceName() (0x21) This read-only string returns a character string where the first byte is the number of characters available ...
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End of Discharge Voltage1 (0x3e) This read-only word returns the first end-of-discharge voltage programmed for the pack. Output: two’s complemented unsigned integer. Returns battery end-of-discharge voltage pro- grammed in EEPROM in mV. End of Discharge VoltageF (0x3f) This read-only ...
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Where LTF is: 0 Temperature > 15°C 1 Temperature < 12°C Bit 0, the Overcurrent flag (OC), is set when Current is 25% greater than the programmed charging current. If the charging current is programmed less than 1024mA, overcurrent is ...
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... An EV2200-40 pro- gramming kit (interface board, software, and cable) for an IBM-compatible PC is available from Benchmarq. The bq2040 uses a 24LC01 or equivalent serial EE- PROM (capable of read operation to 2.0V) for storing the various initial values, calibration data, and string infor- mation ...
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Table 8. Error Codes (BatteryStatus() (0x16)) Error Code OK 0x0000 Busy 0x0001 ReservedCommand 0x0002 UnsupportedCommand 0x0003 AccessDenied 0x0004 Overflow/Underflow 0x0005 BadSize 0x0006 UnknownError 0x0007 Note: Reading the bq2040 after an error clears the error code. Access read/write bq2040 processed the ...
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Bit Name OVER_CHARGED_ALARM TERMINATE_CHARGE_ALARM OVER_TEMP_ALARM TERMINATE_DISCHARGE_ALARM REMAINING_CAPACITY_ALARM REMAINING_TIME_ALARM Bit Name INITIALIZED DISCHARGING FULLY_CHARGED FULLY_DISCHARGED Table 9. BatteryStatus Bits Alarm Bits Set When: The bq2040 detects cur- rent taper termination. (Note and current taper ...
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Table 10. Example Register Contents EEPROM EEPROM Address Hex Contents Low High Low Description Byte Byte Byte EEPROM 0x00 64 length EEPROM check 1 0x01 5b Remaining time 0x02 0x03 0a alarm Remaining 0x04 0x05 f0 capacity alarm Reserved 0x06 ...
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Table 10. Example Register Contents (Continued) EEPROM EEPROM Hex Address Contents Low High Low Byte Byte Byte Description Reserved 0x2f 00 Li-Ion taper 0x38 0x39 10 current M a xim u m overch a rge 0x3a 0x3b 9c limit ...
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Table 10. Example Register Contents (Continued) EEPROM EEPROM Address Contents Low High Low Description Byte Byte Byte Digital filter 0x4d 96 Current integra- 0x4e 40 1 tion gain Self-discharge rate 0x4f 2d 1 Voltage gain 0x56 0x57 17 Reserved 0x58 ...
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Table 11. Example Register Contents (String Data) 0x String Description Address X0 0x20- Manufacturer name 09 0x2b 0x30- Device name 06 0x37 0x40- Device chemistry 04 0x45 0x50- Manufacturer data 05 0x55 ...
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Absolute Maximum Ratings Symbol Parameter V Relative All other pins Relative REF Relative Relative Operating tempera- T OPR ture Note: Permanent device damage may occur ...
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Recommended DC Operating Conditions Symbol Parameter V Supply voltage CC Reference at 25°C V REF Reference at -40°C to +85°C R Reference input impedance REF I Normal operation CC V Battery input input impedance SBmax I ...
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AC Specifications Symbol Parameter F SMBus operating frequency SMB Bus free time between stop and T BUF start condition Hold time after (repeated) start T HD:STA condition T Repeated start condition setup time SU:STA T Stop condition setup time SU:STO ...
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SOIC Narrow (SN 16-Pin SN ( SOIC Narrow ) Dimension All dimensions are in inches. .004 30 Minimum Maximum 0.060 ...
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Data Sheet Revision History ChangeNo. Page No Updated recommended application schematic Changed overcurrent fault conditon for ChargingCurrent < 1024mA 4Hz operation of LED clarification Added descriptions for bits 7 and 13 of ...
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... PACKAGING INFORMATION (1) Orderable Device Status BQ2040SN-C408 ACTIVE BQ2040SN-C408G4 ACTIVE BQ2040SN-C408TR ACTIVE BQ2040SN-C408TRG4 ACTIVE BQ2040SN-D111 ACTIVE BQ2040SN-D111G4 ACTIVE BQ2040SN-D111TR ACTIVE BQ2040SN-D111TRG4 ACTIVE (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. ...
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... TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Type Drawing BQ2040SN-C408TR SOIC BQ2040SN-D111TR SOIC PACKAGE MATERIALS INFORMATION Pins SPQ Reel Reel Diameter Width (mm) W1 (mm 2500 330.0 16 2500 330.0 16.4 Pack Materials-Page (mm) (mm) (mm) (mm) (mm) Quadrant 6.5 10.3 2.1 8 ...
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... Device Package Type BQ2040SN-C408TR SOIC BQ2040SN-D111TR SOIC PACKAGE MATERIALS INFORMATION Package Drawing Pins SPQ Length (mm 2500 D 16 2500 Pack Materials-Page 2 22-Sep-2009 Width (mm) Height (mm) 346.0 346.0 33.0 346.0 346.0 33.0 ...
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Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the ...