Texas Instruments bq24010/2 User manual

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January 2003 PMP Portable Power
User’s Guide
SLUU125A

IMPORTANT NOTICE
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 latest relevant information before placing
ordersandshouldverifythatsuchinformationiscurrentandcomplete.AllproductsaresoldsubjecttoTI’sterms
and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI
deems necessary to support this warranty. Except where mandated by government requirements, testing of all
parameters of each product is not necessarily performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for
their products and applications using TI components. To minimize the risks associated with customer products
and applications, customers should provide adequate design and operating safeguards.
TIdoesnotwarrantorrepresentthatanylicense, eitherexpress orimplied, isgranted underanyTIpatentright,
copyright,maskworkright,orotherTIintellectualpropertyrightrelatingtoanycombination,machine,orprocess
inwhichTIproductsorservicesareused.InformationpublishedbyTIregardingthird–partyproductsorservices
does not constitute a license from TI to use such products or services or a warranty or endorsement thereof.
Use of such information may require a license from a third party under the patents or other intellectual property
of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of information in TI data books or data sheets is permissible only if reproduction is without
alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction
of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for
such altered documentation.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that
product or service voids all express and any implied warranties for the associated TI product or service and
is an unfair and deceptive business practice. TI is not responsible or liable for any such statements.
Mailing Address:
Texas Instruments
Post Office Box 655303
Dallas, Texas 75265
Copyright 2003, Texas Instruments Incorporated

EVM IMPORTANT NOTICE
Texas Instruments (TI) provides the enclosed product(s) under the following conditions:
Thisevaluationkit being soldbyTI is intendedforuse for ENGINEERING DEVELOPMENT OR EVALUATION
PURPOSES ONLY and is not considered by TI to be fit for commercial use. As such, the goods being provided
may not be complete in terms of required design-, marketing-, and/or manufacturing-related protective
considerations, including product safety measures typically found in the end product incorporating the goods.
As a prototype, this product does not fall within the scope of the European Union directive on electromagnetic
compatibility and therefore may not meet the technical requirements of the directive.
ShouldthisevaluationkitnotmeetthespecificationsindicatedintheEVMUser’sGuide,thekitmaybereturned
within 30 days from the date of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE
WARRANTY MADE BY SELLER TO BUYER AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED,
IMPLIED,ORSTATUTORY,INCLUDINGANYWARRANTY OFMERCHANTABILITYOR FITNESSFOR ANY
PARTICULAR PURPOSE.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user
indemnifies TI from all claims arising from the handling or use of the goods. Please be aware that the products
receivedmaynotberegulatorycompliant oragency certified (FCC,UL, CE,etc.). Dueto theopen construction
oftheproduct,itistheuser’sresponsibilitytotakeanyandallappropriateprecautionswithregardtoelectrostatic
discharge.
EXCEPT TO THE EXTENT OF THE INDEMNITY SET FORTH ABOVE, NEITHER PARTY SHALL BE LIABLE
TO THE OTHER FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
TI currently deals with a variety of customers for products, and therefore our arrangement with the user is not
exclusive.
TI assumes no liability for applications assistance, customer product design, software performance, or
infringement of patents or services described herein.
Please read the EVM User’s Guide and, specifically, the EVM Warnings and Restrictions notice in the EVM
User’sGuidepriortohandlingtheproduct.Thisnoticecontainsimportantsafetyinformationabouttemperatures
and voltages. For further safety concerns, please contact the TI application engineer.
Persons handling the product must have electronics training and observe good laboratory practice standards.
No license is granted under any patent right or other intellectual property right of TI covering or relating to any
machine, process, or combination in which such TI products or services might be or are used.
Mailing Address:
Texas Instruments
Post Office Box 655303
Dallas, Texas 75265
Copyright 2003, Texas Instruments Incorporated

EVM WARNINGS AND RESTRICTIONS
ItisimportanttooperatethisEVMwithintheinputvoltagerangeof5.6Vandtheoutputvoltage
range of 0 V and 4.25 V.
Exceeding the specified input range may cause unexpected operation and/or irreversible
damage to the EVM. If there are questions concerning the input range, please contact a TI
field representative prior to connecting the input power.
Applyingloadsoutsideofthespecifiedoutputrangemayresultinunintendedoperationand/or
possible permanent damage to the EVM. Please consult the EVM User’s Guide prior to
connecting any load to the EVM output. If there is uncertainty as to the load specification,
please contact a TI field representative.
Duringnormaloperation,somecircuitcomponentsmayhavecasetemperaturesgreaterthan
60°C.TheEVM isdesignedto operateproperlywith certaincomponentsabove 60°C aslong
astheinputandoutput rangesare maintained.Thesecomponentsincludebut arenot limited
tolinearregulators,switchingtransistors,passtransistors,andcurrentsenseresistors.These
typesof devicescanbeidentifiedusingtheEVM schematiclocated intheEVMUser’sGuide.
When placing measurement probes near these devices during operation, please be aware
that these devices may be very warm to the touch.
Mailing Address:
Texas Instruments
Post Office Box 655303
Dallas, Texas 75265
Copyright 2003, Texas Instruments Incorporated

Contents
v
Contents
1 Introduction 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1 Background 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Performance Specification Summary 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 Test Summary 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 I/O and Jumper Connections 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Test Procedure 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2.1 Equipment 2-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2.2 Equipment Setup 2-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2.3 Procedure 2-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 Schematic, Physical Layouts, and Bill of Materials 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1 Schematic 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Physical Layouts 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.1 Board Layout 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3 Bill of Materials 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4 Reference 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figures
2–1 Load Test Board 2-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–1 EVM Schematic Diagram 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–2 Assembly View 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–3 Top Layer 3-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–4 Bottom Layer 3-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tables
1–1 Performance Specification Summary 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–1 Bill of Materials 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Contents
vi

1-1
Introduction
This user’s guide describes the bq24010/2 (bqTINY) evaluation module.
The EVM provides a convenient method for evaluating the performance of a
charge-management solution for portable applications using the bq24010/2
product family. A complete designed and tested charger is presented. The
charger is designed to deliver up to 1.0 A of continuous charge current, but is
programmed for 0.7 A, for single-cell Li-Ion or Li-Pol applications using a dc
power supply.
Topic Page
1.1 Background 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Performance Specification Summary 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 1
bqTINY is a trademark of Texas Instruments.

Background
1-2
1.1 Background
The bqTINY series are highly integrated Li-Ion and Li-Pol linear charge
management devices targeted at space limited portable applications. In a
small package, the bqTINY series offer integrated PowerFET and current
sensor, reverse blocking diode, high accuracy current and voltage regulation,
charge status, and charge termination.
The bqTINY charges the battery in three phases: conditioning, constant
current, and constant voltage. Charge is terminated on the basis of minimum
current. An internal charge timer provides backup safety for charge
termination. The bqTINY automatically restarts the charge if the battery
voltage falls below an internal threshold. The bqTINY automatically enters
sleep mode when VCC supply is removed.
In addition to the standard features, different versions of the bqTINY offer a
multitude of additional features. These include temperature-sensing input for
detecting hot or cold battery packs, power good (PG) output indicating the
presence of the ac adapter, a TTL-level charge enable input (CE) to disable
or enable the charge process, and a TTL-level timer and termination-enable
(TTE)input to disableorenablethe fast-charge timer andchargetermination.
1.2 Performance Specification Summary
This section summarizes the performance specifications of the EVM.
Table 1–1 gives the performance specifications of the EVM.
Table 1–1.Performance Specification Summary
Specification Test Conditions Min Typ Max Units
Input dc voltage, VI(DC) VREG+0.5 5.0 5.2†V
Battery charge current, IO(CHG) See note 0.7†A
Power dissipation (V(DC+) –V(BAT+))*I(CHG) 1.5 W
†This input voltage maximum is a function of the maximum allowable power dissipation on the IC. The current level is pro-
grammed for 0.7 amps. If the programmed charge is changed, then the maximum input voltage needs to be adjusted.
PmaxIC = 1.5 Watt = ICHG(VDC+ –VBAT+).

2-1
Test Summary
Test Summary
Thischaptershowsthetestsetupsusedandthetestsperformedinevaluating
the EVM.
Setup: The bq24010/2 EVM board requires a 5-VDC, 1-A power source to
provideinputpowerandasingle-cellLi-IonorLi-Polbatterypack.Thetestset-
upconnectionsandjumpersettingselectionsareconfiguredforastand-alone
evaluation but can be changed to interface with external hardware, such as a
microcontroller.
Topic Page
2.1 I/O and Jumper Connecations 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Test Procedure 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 2

I/O and Jumper Connections
2-2
2.1 I/O and Jumper Connections
Jack Connect To:
J1–DC+ Power supply positive, preset to 5.0VDC, 1-A current limit.
J1–DC–Power supply ground
J2–BAT+ Positive battery pack terminal
J2–BAT–Negative battery pack terminal
J2–TS NC
J2–BAT–NC
J3–STAT1 ExternalhardwareifJ4-EXTisjumpered(Notjumperedfromfactory)
J3–STAT2 ExternalhardwareifJ5-EXTisjumpered(Not jumperedfromfactory)
J3–DC–Return for J3 signals
J3–PG Externalhardware ifJ6–EXTifjumpered(Notjumperedfromfactory)
J4 (Jumper) STAT1 indication location –LED (EVM) | EXT
J5 (Jumper) STAT2 indication location –LED (EVM) | EXT
J6 (Jumper) PG indication location –LED (EVM) | EXT
Note: Factory jumper selections shown in bold.
2.2 Test Procedure
Setuptheevaluationboardasdescribedabove,bymakingthenecessaryI/O
connections and jumper selections. Before test and evaluation, it is
important to verify that the maximum power dissipation on the IC is not
exceeded: P(MAX) = 1.5 watts.
1) Turn on the power supply, which was preset to 5.0 VDC and 1 A for the
current limit setting.
2) The bq24010/2 enters preconditioning mode if the battery is below the
V(LOWV) threshold. In this mode, the bq24010/2 precharges the battery
withalowcurrent(typicallyIO(CHG)/10=0.7A/10=70mA)untilthebattery
voltage reaches the V(LOWV) threshold or until the precharge timer
expires. If the timer expires, then the charge current is terminated, the
bq24010/2entersfaultmode,andbothLEDsturnoff.Togglinginputpower
or battery replacement resets fault mode.
3) Once the battery voltage is above the V(LOWV) threshold, the battery
enters fast-charge mode. This EVM is programmed for 0.7 amps of fast
charging current.
4) Once the battery reaches voltage regulation (4.2 V), the current tapers
down as the battery reaches its full capacity.
5) The battery remains at the fast-charge mode until the fast-charge timer
expires,thechargetapertimeexpires,orthechargeterminationthreshold
is reached.
6) If the battery discharges to the recharge threshold, the charger starts fast
charging.

Test Procedure
2-3
Test Summary
In place of a battery, a source meter that can sink current can easily be
adjusted to test each mode.
Another way to briefly see each mode on a scope is to connect a 1-mF
capacitor and a 10-kΩresistor on the output in place of a battery to observe
the power-up and cycling between voltage regulation and fast charge via the
refresh threshold.
The difference between the bq2401x parts, where x is a 0 or 2, is as follows:
The functions on the 0 part are power good output (PG) for pin 7 and
temperaturesenseInput (TS)forpin8. Onpart2,pin 8ischarge enable(CE).
From the factory, the CE pin has a pulldown resistor and the TS pin is set at
50%ofVCC,whereapplicable.Thesesignals,ifapplicable,areavailableatthe
connectors for external control.
Note:
Because of the battery-detection circuit, it is not possible to switch-in static
load resistors to jump between regulation and constant-current modes. An
alternate procedure described below uses a dynamic load to replace the
battery circuit. That procedure allows testing of each mode.
This is an alternative way of testing the EVM using a dynamic load board in
place of a battery. The circuit is adjusted to work with the displayed parts and
their inherent thresholds. The sequence of the test procedure is important
becauseof the active battery-detectioncircuit,refreshfeature,and precharge
and fast-charge current levels. (Switching load in or out has different results
in different modes.) No damage should occur, but results might be different
than anticipated if procedure is altered.

Test Procedure
2-4
2.2.1 Equipment
1) Power source: current-limited 5-V lab supply with its current limit set to
1.0 A ±0.1 A
2) Two Fluke 75, equivalent or better
3) Oscilloscope –TDS220 or better
4) Load test board (See Figure 2–1.)
Figure 2–1.Load Test Board
C1
2000 µF
25 V
8
Power Supply
5.1 V ±0.1 V
Current Limit
1 A ±0.1 A
+
–
DMM DC+
DC–
UUT
bq24010/2 EVM
BAT+
BAT–
BAT+
BAT–
DMM
Volts S4
R3
3 kΩ
0.25 W
S1
R6
10 kΩ
0.25 W
S2
R4
66.5 Ω
0.25 W
765
R5
66.5 Ω
0.25 W
Q1
Si4410DY
321
D1
1N4148
S3
R7
10 kΩ
0.25 W
8765
Q2
Si4410DY
321
44
R1
5 Ω
5 W
2.2.2 Equipment Setup
1) Connect the load board to the BAT+ and BAT–. Set SW1 through SW4 in
the closed position.
2) Connect a voltage meter to the BAT+/BAT–output to monitor the output
voltage (Range is 0 to 5 V).
3) Setthelabsupplyfor5.1V±0.1VDC,1.0±0.1Acurrentlimitandthenturn
off supply. Connect the source supply to a current meter and to J1, noting
polarity. (You may use an internal source current meter if it has 5% or
better accuracy.)
4) Install shunt jumpers on the LED pins 1 and 2 of each header J4, J5, and
J6.
5) Connect the scope to the output, BAT+.
2.2.3 Procedure
1) Ensure that equipment setup steps are followed. (Switches should be in
the closed position, shunts installed, and power source set to 5.1V/-0.1V.
Turn on the power source.
2) Verify that output voltage BAT+ charges up to between 2.5 V and 2.9 V,
and the red LED (D1) and green LED (D3) are lit.
3) Open switch SW2, and then close switch SW2.

Test Procedure
2-5
Test Summary
4) Verify that output voltage BAT+ settles between 3.2 V and 3.95 V.
5) Verify that the input current is between 0.69 A and 0.75 A.
6) Open switch SW3.
7) Verify that the input current is between 100 mA and 150 mA.
8) Verify the output voltage BAT+ is between 4.150 VDC and 4.250 VDC.
9) Open switch SW2.
10) Verify with a scope (250 ms/div, 1 V/div) that output BAT+ charges and
discharges are between the maximum limits of 3 V and 4.35 V, with a
period between 600 ms and 850 ms.
11) Verify that the LEDs flash between RED (D1) and GREEN (D2, mostly on
green).
12) Open switch SW4 and verify that D1 and D2 are off and D3 is on.
13) Verify,withascope on BAT+, a square wave between the maximum limits
of 1.3 and 4.35 VDC and a frequency between 3.5 and 4.5 Hz.
14) Closeswitches SW2, SW3,andSW4(all switches should beclosednow)
and power down the supply.
15) The EVM is good if all tests are passed.

3-1
Schematic, Physical Layouts, and Bill of Materials
Schematic, Physical Layouts, and
Bill of Materials
Thischaptercontainstheschematicdiagram,theboardlayoutsandassembly
drawings, and the bill of materials required for the EVM.
Topic Page
3.1 Schematic 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Physical Layouts 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3 Bill of Materials 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4 Reference 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 3

Schematic
3-2
3.1 Schematic Figure 3–1.EVM Schematic Diagram
1
DC+
J1
DC–2
R1
1.5 kΩ
D1
Red D2 Green
R2
1.5 kΩ
C3
0.47 µF
R5
1.5 kΩ
U1
bq24010
OUTIN
110
PWP
BATVCC
29
TSSTAT1
38
PG
STAT2
47
ISETVSS
56
D3
Green
11 R3
1 MΩ2R6
1 MΩ
C1
1 µF
10 V
TP1
TP2
R4
1.13 kΩ
C2
1 µF
10 V
1
4
3
2
1
BAT+
BAT–
TS(/CE)
BAT–2
J2
J3
1
2
3
4
STAT1
STAT2
DC–
PG
1 2 3J6
LED EXT
PG JUMPER
LED EXT
STAT2 JUMPER
LED EXT
STAT1 JUMPER
Not installed
1
bq24012 EVM (IC)–TS pin becomes /CE. R6 becomes 10 kΩand R3 is removed
2
1 2 3J5 1 2 3J4

Physical Layouts
3-3
Schematic, Physical Layouts, and Bill of Materials
3.2 Physical Layouts
3.2.1 Board Layout
Figure 3–2 shows the assembly view of the EVM. Figure 3–3 shows the top
layer. Figure 3–4 shows the bottom layer.
Figure 3–2.Assembly View

Physical Layouts
3-4
Figure 3–3.Top Layer
Figure 3–4.Bottom Layer

Bill of Materials
3-5
Schematic, Physical Layouts, and Bill of Materials
3.3 Bill of Materials
Table 3–1 lists materials required for the EVM.
Table 3–1.Bill of Materials
Item# bq24010
–1 bq24012 –2 Ref Des Description Size MFR Part Number
1 0 0 C1 Capacitor, ceramic, X5R,
1 µF, 10 V 805 Panasonic ECJ-2YB1A105K
2 1 1 C2 Capacitor, ceramic, X5R,
1 µF, 10 V 805 Panasonic ECJ-2YB1A105K
3 1 1 C3 Capacitor, ceramic, X7R,
0.47 µF, 16 V 805 Panasonic ECJ-2YB1C474K
4 1 1 D1 Diode, LED, red, 1.8 V,
20 mA, 20 mcd 603 Lite-On 160-1181-1-ND
5 2 2 D2, D3 Diode, LED, green, 2.1 V,
20 mA, 6 mcd 603 Lite-On 160-1183-1-ND
6 1 1 J1 Terminal block, 2 pin, 6 A,
3,5 mm 0.27 ×0.25 OST ED1514
7 2 2 J2, J3 Terminal block, 4 pin, 6 A,
3,5 mm 0.55 ×0.25 OST ED1516
8 3 3 J4, J5,
J6 Header, 3 pin, 100 mil spacing, (36-pin strip) 0.100 ×3 Sullins PTC36SAAN
9 3 3 R1, R2,
R5 Resistor, chip, 1.5 kΩ, 1/16 W, 1% 603 Std Std
10 2 0 R3, R6 Resistor, chip, 1 MΩ,
1/16 W, 1% 602 Std Std
11 0 1 R6 Resistor, chip, 10 kΩ,
1/16 W, 1% 603 Std Std
12 1 1 R4 Resistor, chip, 1.3 kΩ,
1/16 W, 1% 603 Std Std
13 1 0 U1 IC, single Li-Ion/Li-Poly,
charge manager MLP10 TI bq24010DRC
14 0 1 U1 IC, single Li-Ion/Li-Poly,
charge manager MLP10 TI bq24012DRC
15 3 3 —Shunt, 100-mil, black 0.100 3M 929950-00
16 1 1 —PCB, bq24010/2,
1.6 in ×1.3 in ×0.031 in Any SLUP162
Notes: 1) These assemblies are ESD sensitive; ESD precautions must be observed.
2) These assemblies must be clean and free from flux and all contaminants. Use of no-clean flux is not acceptable.
3) These assemblies must comply with workmanship standards IPC-A-610 Class 2.
4) Reference designators marked with an asterisk (**) cannot be replaced by substitutes. All other components can
be replaced with equivalent manufacturer components.
3.4 Reference
1) bq2401x data sheet (SLUS530)