Texas Instruments bq20z95EVM-001 User manual

User's GuideSLUU275 – October 2006
bq20z95EVM-001 SBS 1.1 Impedance Track™ TechnologyEnabled Battery Management Solution Evaluation Module
This evaluation module (EVM) is a complete evaluation system for the bq20z95/bq29412 batterymanagement system. The EVM includes one bq20z95/bq29412 circuit module, an EV2300 PC interfaceboard for gas gauge interface, a PC USB cable, and Windows™-based PC software. The circuit moduleincludes one bq20z95 integrated circuit (IC), one bq29412 IC, and all other onboard componentsnecessary to monitor and predict capacity, perform cell balancing, monitor critical parameters, protect thecells from overcharge, over-discharge, short-circuit, and overcurrent in 2-, 3- or 4-series cell Li-ion orLi-polymer battery packs. The circuit module connects directly across the cells in a battery. With theEV2300 interface board and software, the user can read the bq20z95 data registers, program the chipsetfor different pack configurations, log cycling data for further evaluation, and evaluate the overallfunctionality of the bq20z95/bq29412 solution under different charge and discharge conditions.
Contents1 Features ....................................................................................................................... 22 bq20z95-Based Circuit Module ............................................................................................ 23 bq20z95 Circuit Module Schematic ....................................................................................... 34 Circuit Module Physical Layouts and Bill of Materials .................................................................. 45 EVM Hardware and Software Setup ...................................................................................... 96 Troubleshooting Unexpected Dialog Boxes .............................................................................. 97 Hardware Connection ....................................................................................................... 98 Operation .................................................................................................................... 119 Calibration Screen.......................................................................................................... 1310 Pro (Advanced) Screen .................................................................................................... 1511 Pack Assembly and The bq20z95 ....................................................................................... 1612 Related Documentation from Texas Instruments ...................................................................... 17Trademarks ................................................................................................................. 17
List of Figures
1 bq20z95EVM-001 Layout (Silk Screen) .................................................................................. 42 Top Assembly ................................................................................................................ 53 Top Layer ..................................................................................................................... 54 Bottom Layer ................................................................................................................. 55 Bottom Assembly ............................................................................................................ 66 Schematic ..................................................................................................................... 87 bq20z95 Circuit Module Connection to Cells and System Load/Charger ........................................... 108 SBS Data Screen........................................................................................................... 119 Data Flash Screen, 1st Level Safety Class ............................................................................. 1210 Calibration Screen.......................................................................................................... 1411 Pro (Advanced) Screen .................................................................................................... 1512 Connection Sequence ..................................................................................................... 1613 Fuel Gauging Command .................................................................................................. 16
List of Tables
1 Ordering Information ........................................................................................................ 22 Components and Flash-Memory Settings for Different Precharge Modes ........................................... 43 Bill of Materials ............................................................................................................... 7
SLUU275 – October 2006 bq20z95EVM-001 SBS 1.1 Impedance Track™ Technology 1Enabled Battery Management Solution Evaluation ModuleSubmit Documentation Feedback

1 Features
1.1 Kit Contents
1.2 Ordering Information
2 bq20z95-Based Circuit Module
2.1 Circuit Module Connections
Features www.ti.com
4 Performance Specification Summary ..................................................................................... 95 Circuit Module to EV2300 Connections ................................................................................. 10
•Complete evaluation system for the bq20z95 SBS 1.1-compliant advanced gas gauge with ImpedanceTrack™ technology and bq29412 independent overvoltage protection IC•Populated circuit module for quick setup•PC software and interface board for easy evaluation•Software that allows data logging for system analysis
•bq20z95/bq29412 circuit module•EV2300 PC interface board•Software CD with the evaluation software•Connection cable to interface board•Set of support documentation•EV2300 USB interface board
Table 1. Ordering Information
EVM PART NUMBER CHEMISTRY CONFIGURATION CAPACITY
bq20z95EVM-001 Li-ion 2, 3, or 4 cell Any
The bq20z95/bq29412-based circuit module is a complete and compact example solution of a bq20z95circuit for battery management and protection of Li-ion or Li-polymer packs. The circuit moduleincorporates a bq20z95 battery monitor IC, bq29412 independent overvoltage protection IC, and all othercomponents necessary to accurately predict the capacity of 2-, 3-, or 4-series cells.
Contacts on the circuit module provide the following connections:•Direct connection to the cells: 1N (BAT-), 1P, 2P, 3P, 4P (BAT+)•To the serial communications port (SMBC, SMBD)•The system load and charger connect across PACK+ and PACK-•To the system-present pin (SYS PRES)
2bq20z95EVM-001 SBS 1.1 Impedance Track™ Technology SLUU275 – October 2006Enabled Battery Management Solution Evaluation Module
Submit Documentation Feedback

2.2 Pin Descriptions
3 bq20z95 Circuit Module Schematic
3.1 Schematic
3.2 Modifications for Choosing Particular Precharge Mode
www.ti.com bq20z95 Circuit Module Schematic
PIN NAME DESCRIPTION
1N -ve connection of first (bottom) cell1P +ve connection of first (bottom) cell2P +ve connection of second cell3P +ve connection of third cell4P +ve connection of fourth (top) cellSMBC Serial communication port clockSMBD Serial communication data portSYS PRES System present pin (if low, system is present)PACK- Pack negative terminalVSS Pack negative terminalPACK+ Pack positive terminal
This section contains information for modifying and choosing a precharge mode for bq20z95/bq29412implementation.
The schematic follows the bill of materials in this user's guide.
In order to charge, the charge FET (CHG-FET) must be turned on to create a current path. When theV
(BAT)
is 0 V and CHG-FET = ON, the V
(PACK)
is as low as the battery voltage. In this case, the supplyvoltage for the device is too low to operate. This function has three possible configurations, and the IC canbe easily configured according to the application needs. The three modes are 0-V Charge FET mode,Common FET mode, and Precharge FET mode.1. 0-V Charge FET mode - Dedicates a precharge current path using an additional FET (ZVCHG-FET) tosustain the PACK+ voltage level.2. Common FET mode - Does not use a dedicated precharge FET. The charge FET (CHG-FET) is set toON state as default.3. Precharge FET mode - Dedicates a precharge current path using an additional open-drain (OD) pindrive FET (PCHG-FET) to sustain the PACK+ voltage level.
To use a particular mode of charging with the EVM, add or remove some elements shown in Table 2 , anduse the given settings of DF.Configuration, ZVCHG1, 0.
SLUU275 – October 2006 bq20z95EVM-001 SBS 1.1 Impedance Track™ Technology 3Enabled Battery Management Solution Evaluation ModuleSubmit Documentation Feedback

3.3 Testing Fuse-Blowing Circuit
4 Circuit Module Physical Layouts and Bill of Materials
4.1 Board Layout
Circuit Module Physical Layouts and Bill of Materials www.ti.com
Table 2. Components and Flash-Memory Settings for Different PrechargeModes
MODE RESISTORS PRECHG FET ZVCHG1 ZVCHG0
1. 0-V Chg (default) R21, R28 Q3 0 02. Common FET R24 Q2 0 13. Precharge R23, R28 Q3 1 0
For more details about precharge operation and mode choices, see the bq20z95 data sheet at(SLUS757 ).
To prevent the loss of board functionality during the fuse-blowing test, the actual chemical fuse is notprovided in the circuit. FET Q4 drives TP3 low if a fuse-blow condition occurs; so, monitoring TP3 can beused to test this condition. Fuse placement on the application board is shown in the bq20z95 data sheetreference-board schematic.
This section contains the board layout, bill of materials, and assembly drawings for the bq20z95/bq29412circuit module.
This section shows the dimensions, PCB layers (Figure 1 through Figure 5 ), and assembly drawing for thebq20z95 module.
Figure 1. bq20z95EVM-001 Layout (Silk Screen)
4bq20z95EVM-001 SBS 1.1 Impedance Track™ Technology SLUU275 – October 2006Enabled Battery Management Solution Evaluation Module
Submit Documentation Feedback

www.ti.com Circuit Module Physical Layouts and Bill of Materials
Figure 2. Top Assembly
Figure 3. Top Layer
Figure 4. Bottom Layer
SLUU275 – October 2006 bq20z95EVM-001 SBS 1.1 Impedance Track™ Technology 5Enabled Battery Management Solution Evaluation ModuleSubmit Documentation Feedback

Circuit Module Physical Layouts and Bill of Materials www.ti.com
Figure 5. Bottom Assembly
6bq20z95EVM-001 SBS 1.1 Impedance Track™ Technology SLUU275 – October 2006Enabled Battery Management Solution Evaluation Module
Submit Documentation Feedback

4.2 Bill of Materials and Schematic
www.ti.com Circuit Module Physical Layouts and Bill of Materials
Table 3. Bill of MaterialsCount RefDes Description Size Mfr Part Number
21 C1–C9, C12, Capacitor, Ceramic, 0.1 µF, 50 V, X7R, 20% 0603 Any STDC13, C15–C18,
C20, C23, C24,C26–C28
1 C11 Capacitor, Ceramic, 0.22 µF, 50 V, X7R, 20% 0603 Any STD
1 C19 Capacitor, Ceramic, 4.7 µF, 10 V, X7R, 20% 0603 Any STD
2 C22, C25 Capacitor, Ceramic, 0.47 µF, 16 V, X7R, 20% 0603 Any STD
3 C10, C14, C21 Capacitor, Ceramic, 1.0 µF, 25 V, X7R, 20% 0805 Any STD
4 D1–D3, D11 Diode, Switching, 150-mA, 75-V, 350mW SOT23 Vishay-Liteon BAS16
2 D4, D5 Diode, Dual, Zener, 5.6V, 300mW SOT23 Vishay- AZ23C5V6Telefunken
5 D6–D10 Diode, LED, Green, Gullwing, GW Type, 20ma, 7.5 0.120 ×0.087 Panasonic LN1361Cmcd typ. inches
1 J1 Header, Friction Lock Ass'y, 4-pin Right Angle, 0.400 ×0.500 Molex 22-05-3041
1 Q1 MOSFET, N-ch, 20-V, 1.3A, 0.16- ΩSOT23 Fairchild NDS331N
2 Q2, Q4 MOSFET, N-ch Logic Level, Power Trench, 30V, 11A, SO8 Fairchild FDS6690A12.5 m Ω
1 Q3 MOSFET, P-ch, 30-V, 8.0-A, 20-m ΩSO8 Siliconix Si4435DY
1 Q6 MOSFET, Nch, 50V, 0.22A, 6 ΩSOT23 Fairchild BSS138
12 R1–R5, R12, Resistor, Chip, 100- Ω, 1/16-W, 5% 0603 Std StdR13, R32–R34,
R38, R39
1 R11 Resistor, Chip, 0.010 Ω, 1-W, xx% 2512 Vishay WSL-2512-010 1%R86
3 R15, R16, R40 Resistor, Chip, 220 k Ω, 1/16-W, 5% 0603 Std Std
1 R17 Resistor, Chip, 300- Ω, 1-W, 10% 2512 WSL-2512-300 1%R86
2 R18, R27 Resistor, Chip, 3.01M Ω, 1/16-W, 5% 0603 Std Std
5 R14, R19, Resistor, Chip, 5.1k Ω, 1/16-W, 5% 0603 Std StdR21–R23
4 R20, R36, R37, Resistor, Chip, 1M Ω, 1/16-W, 5% 0603 Std StdR41
2 R24, R28 Resistor, Chip, 100k Ω, 1/16-W, 5% 0603 Std Std
2 R25, R29 Resistor, Chip, 8.45k Ω, 1/16-W, 1% 0603 Std Std
2 R26, R30 Resistor, Chip, 61.9k Ω, 1/16-W, 1% 0603 Std Std
7 R6–R10, R31, Resistor, Chip, 1k Ω, 1/16-W, 5% 0603 Std StdR35
2 RT1, RT2 Thermistor, 10k Ω0.095 ×0.150 Semitec NTC103AT
1 SW1 Switch, Push button, Momentary, N.O. Low Profile 5 mm ×5 mm Panasonic EVQPLCxxxx
2 TB1, TB4 Terminal Block, 2-pin, 6-A, 3,5mm 0.27 ×0.25 OST ED1514
2 TB2, TB3 Terminal Block, 3-pin, 6-A, 3,5mm 0.41 ×0.25 OST ED1515
1 TP1 Test Point, Black, Thru Hole Color Keyed 0.100 ×0.100 inch Keystone 5001
1 TP3 Test Point, White, Thru Hole Color Keyed 0.100 ×0.100 inch Keystone 5002
1 U1 IC, Voltage Protection for 2, 3, 4 Cell Lion , 2nd SSOP-08 TI BQ29412DCTProtection, 4.45 V OVP
1 U2 IC, Cool-GG Programmable Battery Management TSSOP30 TI bq20z95DBT
SLUU275 – October 2006 bq20z95EVM-001 SBS 1.1 Impedance Track™ Technology 7Enabled Battery Management Solution Evaluation ModuleSubmit Documentation Feedback

4.3 bq20z95/bq29412 Circuit Module Performance Specification Summary
Circuit Module Physical Layouts and Bill of Materials www.ti.com
Figure 6. Schematic
This section summarizes the performance specifications of the bq20z95/bq29412 circuit module.
8bq20z95EVM-001 SBS 1.1 Impedance Track™ Technology SLUU275 – October 2006Enabled Battery Management Solution Evaluation Module
Submit Documentation Feedback

5 EVM Hardware and Software Setup
5.1 System Requirements
5.2 Software Installation
6 Troubleshooting Unexpected Dialog Boxes
7 Hardware Connection
www.ti.com EVM Hardware and Software Setup
Table 4. Performance Specification Summary
Specification Minimum Typical Maximum Units
Input voltage Pack+ to Pack– 6 15 25 VCharge and discharge current 0 2 7 A
This section describes how to install the bq20z95EVM-001 PC software, and how to connect the differentcomponents of the EVM.
The bq20z95EVSW software requires Windows™ 2000 or Windows XP. Drivers for Windows 98SE areprovided, but Microsoft™ no longer supports Windows 98; and there may be issues in Windows 98 withUSB driver support. The EV2300 USB drivers have been tested for Windows 98SE, but no assurance ismade for problem-free operation with specific system configurations.
Find the latest software version in the bq20z95 tool folder on power.ti.com . Use the following steps toinstall the bq20z95EVSW software:1. Copy the files from the CD into the temporary directory you selected, open the archive TI USBDRVRS.zip, and extract its contents in a subdirectory/drivers. Choose preserve directory structureoption when extracting. Alternatively, run setup.exe from the same directory.2. Plug the EV2300 into a USB port.3. Wait until system prompt new hardware found appears. Choose select location manually, and use thebrowse button to point to subdirectory TIUSBWin2K-XP-1.4. Answer continue to the warning that drivers are not certified with Microsoft.5. After installation finishes, another system prompt new hardware found appears. Repeat procedureabove, but point to subdirectory TIUSBWin2K-XP-26. Answer continue to the warning that drivers are not certified with Microsoft. Installation of drivers isnow finished.7. For Windows 98, point to directory TIUSBWin98.8. Return to the temporary directory where you extracted files; double-click on the setup.exe icon toinstall EV Software.
If files were downloaded from the Web:1. Open the archive containing the installation package, and copy its contents in a temporary directory.2. Follow the preceding steps 1–8.
Ensure that the files were extracted from the zip file using the Preserve Folder names option.
Ensure that all the files were extracted from the zip file.
The user that is downloading the files must be logged in as the administrator.
The driver is not signed, so the administrator must allow installation of unsigned drivers in the operatingsystem policy.
The bq20z95EVM-001 comprises three hardware components: the bq20z95/bq29412 circuit module, theEV2300 PC interface board, and the PC.
SLUU275 – October 2006 bq20z95EVM-001 SBS 1.1 Impedance Track™ Technology 9Enabled Battery Management Solution Evaluation ModuleSubmit Documentation Feedback

7.1 Connecting bq20z95/bq29412 Circuit Module to Battery Pack
7.2 PC Interface Connection
Hardware Connection www.ti.com
Figure 7 shows how to connect the bq20z95/bq29412 circuit module to the cells and system load/charger.
The cells should be connected in the following order:1. 4-Cell Pack: 1N (BAT–), 1P, 2P, 3P, and 4P (see Section 2.1 for definitions).2. 3-Cell Pack: 1N (BAT–), 1P, 2P, and then connect 4P and 3P together.3. 2-Cell Pack: 1N (BAT–), 1P, and then connect 4P, 3P, and 2P together
To start charge or discharge test, connect PRES pin to PACK- pin to set SYS PRES state. To test sleepmode, disconnect the PRES pin.
Figure 7. bq20z95 Circuit Module Connection to Cells and System Load/Charger
The following steps configure the hardware for interface to the PC:1. Connect the bq20z95-based smart battery to the EV2300 using wire leads as shown in Table 5 .
Table 5. Circuit Module to EV2300 Connections
bq20z95-Based Battery EV2300
SMBD SMBDSMBC SMBCVSS GND
2. Connect the PC USB cable to the EV2300 and the PC USB port.
The bq20z95EVM-001 is now set up for operation.
10 bq20z95EVM-001 SBS 1.1 Impedance Track™ Technology SLUU275 – October 2006Enabled Battery Management Solution Evaluation Module
Submit Documentation Feedback