Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsDev KitsPCB design board

HostSystem

SingleCellLi-lon

BatteryPack

PACK-

PROTECTION

CHG

DSG

Temp

Sense

SOC_INT

Current

Sense

PACK+

Voltage

Sense

BAT_GD

Low

FETs

bq27505

Power

Management

Controller

VCC

DATA

LDO

I2C

Battery

Not Recommended for New Designs

bq27505

www.ti.com

SLUS884–FEBRUARY 2009

System-Side Impedance Track™ Fuel Gauge

Check for Samples: bq27505

1 INTRODUCTION

1.1 FEATURES 1.2 APPLICATIONS

123

• Battery Fuel Gauge for 1-Series Li-Ion

• Smartphones

Applications

• PDAs

• Resides on System Main Board

• Digital Still and Video Cameras

– Works With Embedded or Removable

• Handheld Terminals

Battery Packs

• MP3 or Multimedia Players

• Uses PACK+, PACK–, and T Battery Terminals

• Microcontroller Peripheral Provides:

1.3 DESCRIPTION

– Accurate Battery Fuel Gauging

– Internal Temperature Sensor for Battery

The Texas Instruments bq27505 system-side Li-Ion

Temperature Reporting

battery fuel gauge is a microcontroller peripheral that

– Battery Low Interrupt Warning

provides fuel gauging for single-cell Li-Ion battery

– Battery Insertion Indicator

packs. The device requires little system

– Configurable Level of State of Charge (SOC)

microcontroller firmware development. The bq27505

Interrupts

resides on the system’s main board and manages an

– State of Health Indicator

embedded battery (non-removable) or a removable

– 96 Bytes of Non-Volatile Scratch-Pad FLASH

battery pack.

• Battery Fuel Gauge Based on Patented

The bq27505 uses the patented Impedance Track™

Impedance Track™ Technology

algorithm for fuel gauging, and provides information

– Models the Battery Discharge Curve for

such as remaining battery capacity (mAh),

Accurate Time-to-Empty Predictions

state-of-charge (%), run-time to empty (min), battery

– Automatically Adjusts for Battery Aging,

voltage (mV), temperature (°C) and state of health

Battery Self-Discharge, and

(%).

Temperature/Rate Inefficiencies

– Low-Value Sense Resistor (10 mΩ or Less)

Battery fuel gauging with the bq27505 requires only

• 400KHz I

C™ Interface for Connection to

PACK+ (P+), PACK– (P–), and Thermistor (T)

System Microcontroller Port

connections to a removable battery pack or

• In a 12-Pin NanoFree™ (CSP) Packaging

embedded battery circuit. The CSP option is a 12-ball

package in the dimensions of 2,43 mm × 1,96 mm

with 0,5 mm lead pitch. It is ideal for space

constrained applications.

TYPICAL APPLICATION

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas

Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

2Impedance Track, NanoFree are trademarks of Texas Instruments.

3400KHz I

C is a trademark of Philips Electronics.

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.

Summary of content (42 pages)

PAGE 1
Not Recommended for New Designs bq27505 www.ti.com SLUS884 – FEBRUARY 2009 System-Side Impedance Track™ Fuel Gauge Check for Samples: bq27505 1 INTRODUCTION 1.1 FEATURES 1.
PAGE 2
bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 www.ti.com These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. 1 2 3 ......................................... 1.1 FEATURES .......................................... 1.2 APPLICATIONS ...................................... 1.3 DESCRIPTION .......................................
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bq27505 Not Recommended for New Designs www.ti.com SLUS884 – FEBRUARY 2009 2 DEVICE INFORMATION 2.1 AVAILABLE OPTIONS PART NUMBER bq27505YZGR-J1 bq27505YZGT-J1 (1) 2.2 (1) (2) FIRMWARE VERSION PACKAGE (1) TA COMMUNICATION FORMAT 2.07 CSP-12 –40°C to 85°C I2C TAPE and REEL QUANTITY 3000 250 For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI website at www.ti.com.
PAGE 4
bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 2.3 www.ti.com PIN ASSIGNMENT CSP-12 (BOTTOM VIEW) CSP-12 (TOP VIEW) A3 B3 C3 D3 D3 C3 B3 A3 A2 B2 C2 D2 D2 C2 B2 A2 A1 B1 C1 D1 D1 C1 B1 A1 Table 2-1. PIN FUNCTIONS TERMINAL NAME NO. TYPE (1) DESCRIPTION SRP A1 IA Analog input pin connected to the internal coulomb counter where SRP is nearest the PACK– connection. Connect to 5-mΩ to 20-mΩ sense resistor.
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bq27505 Not Recommended for New Designs www.ti.com SLUS884 – FEBRUARY 2009 3 ELECTRICAL SPECIFICATIONS 3.1 ABSOLUTE MAXIMUM RATINGS over operating free-air temperature range (unless otherwise noted) (1) PARAMETER VALUE UNIT VCC Supply voltage range –0.3 to 2.75 V VIOD Open-drain I/O pins (SDA, SCL, SOC_INT) –0.3 to 6 V VBAT BAT input pin –0.3 to 6 VI Input voltage range to all other pins (BI/Tout, TS, SRP, SRN, BAT_GD) Human-body model (HBM), BAT pin ESD –0.3 to VCC + 0.3 V 1.
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bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 3.3 www.ti.com POWER-ON RESET TA = –40°C to 85°C, typical values at TA = 25°C and VBAT = 3.6 V (unless otherwise noted) PARAMETER TEST CONDITIONS VIT+ Positive-going battery voltage input at VCC VHYS Power-on reset hysteresis 3.4 MIN TYP MAX UNIT 2.09 2.20 2.31 V 45 115 185 mV INTERNAL TEMPERATURE SENSOR CHARACTERISTICS TA = –40°C to 85°C, 2.4 V < VCC < 2.6 V; typical values at TA = 25°C and VCC = 2.
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bq27505 Not Recommended for New Designs www.ti.com 3.8 SLUS884 – FEBRUARY 2009 ADC (TEMPERATURE AND CELL MEASUREMENT) CHARACTERISTICS TA = –40°C to 85°C, 2.4 V < VCC < 2.6 V; typical values at TA = 25°C and VCC = 2.5 V (unless otherwise noted) PARAMETER VIN(ADC) Input voltage range tADC_CONV Conversion time TEST CONDITIONS MIN ZADC1 3.
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bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 www.ti.com I2C-COMPATIBLE INTERFACE COMMUNICATION TIMING CHARACTERISTICS 3.10 TA = –40°C to 85°C, 2.4 V < VCC < 2.6 V; typical values at TA = 25°C and VCC = 2.5 V (unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP MAX UNIT tr SCL/SDA rise time 300 ns tf SCL/SDA fall time 300 ns tw(H) SCL pulse duration (high) 600 ns tw(L) SCL pulse duration (low) 1.
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bq27505 Not Recommended for New Designs www.ti.com SLUS884 – FEBRUARY 2009 4 GENERAL DESCRIPTION The bq27505 accurately predicts the battery capacity and other operational characteristics of a single Li-based rechargeable cell. It can be interrogated by a system processor to provide cell information, such as time-to-empty (TTE), time-to-full (TTF) and state-of-charge (SOC) as well as SOC interrupt signal to the host. Information is accessed through a series of commands, called Standard Commands.
PAGE 10
bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 4.1 www.ti.com DATA COMMANDS 4.1.1 STANDARD DATA COMMANDS The bq27505 uses a series of 2-byte standard commands to enable system reading and writing of battery information. Each standard command has an associated command-code pair, as indicated in Table 4-1.
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bq27505 Not Recommended for New Designs www.ti.com 4.1.1.1 SLUS884 – FEBRUARY 2009 Control( ): 0x00/0x01 Issuing a Control( ) command requires a subsequent 2-byte subcommand. These additional bytes specify the particular control function desired. The Control( ) command allows the system to control specific features of the bq27505 during normal operation and additional features when the bq27505 is in different access modes, as described in Table 4-2. Table 4-2.
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bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 www.ti.com 4.1.1.1.1 CONTROL_STATUS: 0x0000 Instructs the fuel gauge to return status information to control addresses 0x00/0x01. The status word includes the following information. Table 4-3.
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bq27505 Not Recommended for New Designs www.ti.com SLUS884 – FEBRUARY 2009 short applied across the sensing resistor (SR) inputs. The difference between the two measurements is the board offset. After a delay of approximately 32 seconds, this offset value is returned to addresses 0x00/0x01 and written to data flash. The CONROL STATUS [BCA] is also set. The user must prevent any charge or discharge current from flowing during the process. This function is only available when the fuel gauge is UNSEALED.
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bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 www.ti.com 4.1.1.1.19 SEALED: 0x0020 Instructs the fuel gauge to transition from the UNSEALED state to the SEALED state. The fuel gauge must always be set to the SEALED state for use in end equipment. 4.1.1.1.20 IT_ENABLE: 0x0021 This command forces the fuel gauge to begin the Impedance Track™ algorithm, sets the IT Enable to 0x01 and causes the [VOK] and [QEN] flags to be set in the CONTROL_STATUS register.
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bq27505 Not Recommended for New Designs www.ti.com 4.1.1.6 SLUS884 – FEBRUARY 2009 Flags( ): 0x0a/0x0b This read-word function returns the contents of the fuel-gauge status register, depicting the current operating status. Table 4-4. Flags Bit Definitions High byte Low byte bit7 OTC – bit6 OTD – bit5 – OCV_GD bit4 – WAIT_ID bit3 CHG_INH BAT_DET bit2 XCHG SOC1 bit1 FC SYSDOWN bit0 CHG DSG OTC = Overtemperature in charge condition is detected. True when set.
PAGE 16
bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 4.1.1.14 www.ti.com StandbyCurrent( ): 0x1a/0x1b This read-only function returns a signed integer value of the measured standby current through the sense resistor. The StandbyCurrent( ) is an adaptive measurement. Initially it reports the standby current programmed in Initial Standby, and after spending several seconds in standby, reports the measured standby current.
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bq27505 Not Recommended for New Designs www.ti.com SLUS884 – FEBRUARY 2009 4.1.1.21 StateofHealth( ): 0x28/0x29 0x28 SOH percentage: this read-only function returns an unsigned integer value, expressed as a percentage of the ration of predicted FCC(25°C, SOH LoadI) over the DesignCapacity(). The FCC(25°C, SOH LoadI) is the calculated full charge capacity at 25°C and the SOH LoadI which is specified in the data flash.
PAGE 18
bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 www.ti.com Table 4-5. Extended Data Commands (continued) NAME BlockDataControl( ) DeviceNameLength( ) DeviceName( ) ApplicationStatus( ) Reserved 4.1.2.1 COMMAND CODE UNITS SEALED ACCESS (1) (2) UNSEALED ACCESS (1) (2) DFDCNTL 0x61 N/A N/A R/W DNAMELEN 0x62 N/A R R DNAME 0x63...0x69 N/A R R APPSTAT 0x6a N/A R R RSVD 0x6b...
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bq27505 Not Recommended for New Designs www.ti.com 4.1.2.7 SLUS884 – FEBRUARY 2009 DeviceNameLength( ): 0x62 UNSEALED and SEALED Access: This byte contains the length of the Device Name. 4.1.2.8 DeviceName( ): 0x63…0x69 UNSEALED and SEALED Access: This block contains the device name that is programmed in Device Name. 4.1.2.9 ApplicationStatus( ): 0x6a This byte function allows the system to read the bq27505 Application Status data flash location. See Table 6-1 for specific bit definitions. 4.1.2.
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bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 4.3 www.ti.com MANUFACTURER INFORMATION BLOCKS The bq27505 contains 96 bytes of user programmable data flash storage: Manufacturer Info Block A, and Manufacturer Info Block B. The method for accessing these memory locations is slightly different, depending on whether the device is in UNSEALED or SEALED modes.
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bq27505 Not Recommended for New Designs www.ti.com 4.4 SLUS884 – FEBRUARY 2009 ACCESS MODES The bq27505 provides three security modes (FULL ACCESS, UNSEALED, and SEALED) that control data flash access permissions, according to Table 4-6. Data Flash refers to those data flash locations, specified in Table 4-7, that are accessible to the user. Manufacture Information refers to the three 32-byte blocks. Table 4-6.
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bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 www.ti.com Table 4-7. Data Flash Summary (continued) Class Subclass ID Subclass Offset Data Type Min Value Max Value Default Value Units Configuration 34 Charge 6 Configuration 34 Charge 8 Suspend Low Temp I2 –400 Suspend High Temp I2 –400 1200 -50 0.1°C 1200 550 0.
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bq27505 Not Recommended for New Designs www.ti.com SLUS884 – FEBRUARY 2009 Table 4-7.
PAGE 24
bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 www.ti.com with SOC and the Qmax value, to determine FullChargeCapacity( ) and StateOfCharge( ), specifically for the present load and temperature. FullChargeCapacity( ) is reported as capacity available from a fully charged battery under the present load and temperature until Voltage( ) reaches the Term Voltage.
PAGE 25
bq27505 Not Recommended for New Designs www.ti.com SLUS884 – FEBRUARY 2009 Table 5-2. Constant-Power Model Used When Load Mode = 1 LoadSelect Value Power Model Used 0 Average discharge power from previous cycle: There is an internal register that records the average discharge power through each entire discharge cycle. The previous average is stored in this register. 1(default) 5.2.
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bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 5.2.8 www.ti.com Qmax 0 and Qmax 1 Generically called Qmax, these dynamic variables contain the respective maximum chemical capacity of the active cell profiles, and are determined by comparing states of charge before and after applying the load with the amount of charge passed. They also correspond to capacity at a very low rate of discharge, such as the C/20 rate.
PAGE 27
bq27505 Not Recommended for New Designs www.ti.com SLUS884 – FEBRUARY 2009 Table 5-3. Operation Configuration Bit Definition High byte Low byte bit7 RESCAP INT_FOCV bit6 BATG_OVR IDSELEN bit5 INT_BREM SLEEP bit4 PFC_CFG1 RMFCC bit3 PFC_CFG0 SOCI_POL bit2 IWAKE BATG_POL bit1 RSNS1 BATL_POL bit0 RSNS0 TEMPS RESCAP = No-load rate of compensation is applied to the reserve capacity calculation. True when set. Default is 0. BATG_OVR = BAT_GD override bit.
PAGE 28
bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 5.3.4 www.ti.com Power Path Control With the BAT_GD Pin The bq27505 must operate in conjunction with other electronics in a system appliance, such as chargers or other ICs and application circuits that draw appreciable power. After a battery is inserted into the system, there should be no charging current or a discharging current higher than C/20, so that an accurate OCV can be read.
PAGE 29
bq27505 Not Recommended for New Designs www.ti.com SLUS884 – FEBRUARY 2009 In PFC 1, the BAT_GD pin is also used to disable battery charging when the bq27505 reads battery temperatures outside the range defined by [Charge Inhibit Temp Low, Charge Inhibit Temp High]. The BAT_GD line is asserted once temperature falls within the range [Charge Inhibit Temp Low + Temp Hys, Charge Inhibit Temp High – Temp Hys]. 5.3.
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bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 5.4 www.ti.com TEMPERATURE MEASUREMENT The bq27505 measures battery temperature via its TS input, in order to supply battery temperature status information to the fuel gauging algorithm and charger-control sections of the gauge. Alternatively, it can also measure internal temperature via its on-chip temperature sensor, but only if the [TEMPS] bit of the Operation Configuration register is cleared.
PAGE 31
Not Recommended for New Designs www.ti.com 5.7 bq27505 SLUS884 – FEBRUARY 2009 POWER MODES The bq27505 has different power modes: BAT INSERT CHECK, NORMAL, SLEEP, SLEEP+ and HIBERNATE. In NORMAL mode, the bq27505 is fully powered and can execute any allowable task. In SLEEP+ mode, both low frequency and high frequency oscillators are active. Although the SLEEP+ has higher current consumption than the SLEEP mode, it is also a reduced power mode.
PAGE 32
bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 5.7.4 www.ti.com SLEEP+ MODE Compared to the SLEEP mode, SLEEP+ mode has the high frequency oscillator in operation. The communication delay could be eliminated. The SLEEP+ is entered automatically if the feature is enabled (CONTROL STATUS [SNOOZE] = 1) and AverageCurrent( ) is below the programmable level Sleep Current. During SLEEP+ mode, the bq27505 periodically takes data measurements and updates its data set.
PAGE 33
bq27505 Not Recommended for New Designs www.ti.com SLUS884 – FEBRUARY 2009 Table 5-6. IWAKE Threshold Settings (1) (1) 5.8.2 RSNS1 RSNS0 IWAKE Vth(SRP–SRN) 0 0 0 Disabled 0 0 1 Disabled 0 1 0 1.25 mV or –1.25 mV 0 1 1 2.5 mV or –2.5 mV 1 0 0 2.5 mV or –2.
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bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 6.1.2 www.ti.com Activities Upon Pack Insertion 6.1.2.1 First OCV and Impedance Measurement At power-up the BAT_GD pin is inactive, so that the system might not obtain power from the battery (this depends on actual implementation). In this state, the battery should be put in a condition with load current less than C/20. Next, the bq27505 measures its first open-circuit voltage (OCV) via the BAT pin.
PAGE 35
bq27505 Not Recommended for New Designs www.ti.com SLUS884 – FEBRUARY 2009 7 COMMUNICATIONS I2C INTERFACE 7.1 The 27505 supports the standard I2C read, incremental read, quick read, one byte write, and incremental write functions. The 7 bit device address (ADDR) is the most significant 7 bits of the hex address and is fixed as 1010101. The 8-bit device address will; therefore, be 0xAA or 0xAB for write or read, respectively.
PAGE 36
bq27505 Not Recommended for New Designs SLUS884 – FEBRUARY 2009 www.ti.com I2C Time Out 7.2 The I2C engine will release both SDA and SCL if the I2C bus is held low for about 2 seconds. If the bq27505 was holding the lines, releasing them will free for the master to drive the lines. If an external condition is holding either of the lines low, the I2C engine will enter the low power sleep mode. I2C Command Waiting time 7.
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Not Recommended for New Designs www.ti.com bq27505 SLUS884 – FEBRUARY 2009 8 REFERENCE SCHEMATICS 8.
PAGE 38
PACKAGE OPTION ADDENDUM www.ti.
PAGE 39
PACKAGE MATERIALS INFORMATION www.ti.com 22-Mar-2012 TAPE AND REEL INFORMATION *All dimensions are nominal Device BQ27505YZGT-J1 Package Package Pins Type Drawing SPQ DSBGA 250 YZG 12 Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) 180.0 8.4 Pack Materials-Page 1 2.1 B0 (mm) K0 (mm) P1 (mm) 2.57 0.81 4.0 W Pin1 (mm) Quadrant 8.
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PACKAGE MATERIALS INFORMATION www.ti.com 22-Mar-2012 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) BQ27505YZGT-J1 DSBGA YZG 12 250 220.0 220.0 34.
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D: Max = 2.46 mm, Min = 2.399 mm E: Max = 1.986 mm, Min =1.
PAGE 42
IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete.