BQ24040, BQ24041, BQ24045
BQ24040,
BQ24041,
BQ24045
SLUS941H – SEPTEMBER
2009 – REVISED
FEBRUARY
2021
SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
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BQ2404x 1A, Single-Input, Single Cell Li-Ion and Li-Pol Battery Charger With Auto
Start
1 Features
3 Description
•
The BQ2404x series of devices are highly integrated
Li-Ion and Li-Pol linear chargers devices targeted at
space-limited portable applications. The devices
operate from either a USB port or AC adapter. The
high input voltage range with input overvoltage
protection supports low-cost unregulated adapters.
•
•
•
•
Charging
– 1% Charge voltage accuracy
– 10% Charge current accuracy
– Pin selectable USB 100 mA and 500 mA
maximum input current limit
– Programmable termination and precharge
threshold, BQ24040 and BQ24045
– High voltage (4.35 V) chemistry support with
BQ24045
Protection
– 30V Input rating; with 6.6 V or 7.1 V input
overvoltage protection
– Input voltage dynamic power management
– 125°C thermal regulation; 150°C thermal
shutdown protection
– OUT Short-circuit protection and ISET short
detection
– Operation over JEITA range via battery NTC –
1/2 fast-charge-current at Cold, 4.06V at Hot,
BQ24040 and BQ24045
– Fixed 10 hour safety timer, BQ24040 and
BQ24045
System
– Automatic termination and timer disable mode
(TTDM) for absent battery pack with thermistor,
BQ24040 and BQ24045
– Status indication – charging and done
– Available in small 2 × 2 mm2 DFN-10 package
– Integrated auto start function for production line
testing, BQ24041
Functional Safety-Capable (BQ24040)
– Documentation available to aid functional safety
system design
Safety-Related Certifications:
– IEC 62368-1 CB Certification (BQ24040,
BQ24045)
The BQ2404x has a single power output that charges
the battery. A system load can be placed in parallel
with the battery as long as the average system load
does not keep the battery from charging fully during
the 10 hour safety timer.
The battery is charged in three phases: conditioning,
constant current and constant voltage. In all charge
phases, an internal control loop monitors the IC
junction temperature and reduces the charge current
if an internal temperature threshold is exceeded.
The charger power stage and charge current sense
functions are fully integrated. The charger function
has high accuracy current and voltage regulation
loops, charge status display, and charge termination.
The pre-charge current and termination current
threshold are programmed through an external
resistor on the BQ24040 and BQ24045. The fast
charge current value is also programmable through an
external resistor.
Device Information
PART NUMBER(1)
PACKAGE
BQ24041
WSON (10)
2.00 mm x 2.00 mm
BQ24045
(1)
For all available packages, see the orderable addendum at
the end of the data sheet.
1.5kW
BQ24040
Adaptor
1 IN
DC+
OUT 10
1.5kW
2 Applications
•
•
•
•
•
TWS Headsets and headphones
Smartwatches and wristbands
Wireless speakers
Mobile POS
Portable medical devices
BODY SIZE (NOM)
BQ24040
GND
1mF
1kW
2 ISET
TS 9
3 VSS
CHG 8
System Load
Battery Pack
++
1mF
4 PRETERM ISET2 7
OR
5 PG
NC 6
VDD
2kW
TTDM/BAT_EN
USB Port
ISET/100/500mA
VBUS
GND
GND
D+
D+
D-
D-
Host
Simplified Schematic
An©IMPORTANT
NOTICEIncorporated
at the end of this data sheet addresses availability, warranty, changes, use in
safety-critical
applications,
Copyright
2021 Texas Instruments
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intellectual property matters and other important disclaimers. PRODUCTION DATA.
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
Table of Contents
1 Features............................................................................1
2 Applications..................................................................... 1
3 Description.......................................................................1
4 Revision History.............................................................. 2
5 Device Comparison......................................................... 4
6 Pin Configuration and Functions...................................4
7 Specifications.................................................................. 6
7.1 Absolute Maximum Ratings........................................ 6
7.2 ESD Ratings............................................................... 6
7.3 Recommended Operating Conditions.........................6
7.4 Thermal Information....................................................7
7.5 Electrical Characteristics.............................................7
7.6 Timing Requirements................................................ 10
7.7 Typical Operational Characteristics (Protection
Circuits Waveforms).................................................... 11
8 Detailed Description......................................................12
8.1 Overview................................................................... 12
8.2 Functional Block Diagram......................................... 13
8.3 Feature Description...................................................14
8.4 Device Functional Modes..........................................17
9 Application and Implementation.................................. 22
9.1 Application Information............................................. 22
9.2 Typical Applications.................................................. 22
10 Power Supply Recommendations..............................29
11 Layout........................................................................... 30
11.1 Layout Guidelines................................................... 30
11.2 Layout Example...................................................... 30
11.3 Thermal Considerations.......................................... 31
12 Device and Documentation Support..........................32
12.1 Device Support....................................................... 32
12.2 Documentation Support.......................................... 32
12.3 Receiving Notification of Documentation Updates..32
12.4 Support Resources................................................. 32
12.5 Trademarks............................................................. 32
12.6 Electrostatic Discharge Caution..............................32
12.7 Glossary..................................................................32
13 Mechanical, Packaging, and Orderable
Information.................................................................... 32
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision G (June 2020) to Revision H (February 2021)
Page
• Added BQ24040, BQ24045 to IEC 62368-1 CB Certification Feature............................................................... 1
• Changed IBD-SINK minimum from 7 mA to 6 mA..................................................................................................7
• Changed IIH maximum from 8 μA to 9.5 μA........................................................................................................7
Changes from Revision F (March 2015) to Revision G (June 2020)
Page
• Added Functional Safety-Capable Feature ........................................................................................................1
• Added IEC 62368-1 Feature...............................................................................................................................1
• Changed Applications.........................................................................................................................................1
• Deleted Disconnect after Detection from Simplified Schematic..........................................................................1
• Changed thermal pad description ......................................................................................................................4
• Added IOUT(SC) test condition ............................................................................................................................. 7
• Changed Figure 7-5 ......................................................................................................................................... 11
• Changed the Section 8.3.4 section ..................................................................................................................14
• Added (BQ24040) to Figure 8-4 and Figure 8-5 .............................................................................................. 18
• Deleted Disconnect after Detection from Figure 9-1 ........................................................................................22
• Added link to BQ24040 Application Report...................................................................................................... 23
• Deleted Disconnect after Detection from Figure 9-20 ......................................................................................27
• Moved Section 11.3 to Layout section ............................................................................................................. 31
Changes from Revision E (February 2014) to Revision F (March 2015)
Page
• Changed the Device Information table header information, and removed the package designation from the
device number ................................................................................................................................................... 1
• Changed the Terminal Configuration and Functions To: Section 6 ....................................................................4
• The storage temperature range has been moved to the Section 7.1 ................................................................ 6
• Changed the Handling Ratings table To: Section 7.2 and updated the guidelines............................................. 6
2
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•
•
BQ24040, BQ24041, BQ24045
SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
Added the package family to the column heading in the Section 7.4................................................................. 7
Added the NOTE to the Section 9 ................................................................................................................... 22
Changes from Revision D (March 2013) to Revision E (February 2014)
Page
• Added Handling Ratings table , Feature Description section, Device Functional Modes section, Application
and Implementation section, Power Supply Recommendations section, Layout section, Device and
Documentation Support section, and Mechanical, Packaging, and Orderable Information section................... 1
• Changed the Dissipation Rating table to the Section 7.4................................................................................... 7
• Changed VO_HT(REG) in the Electrical Characteristics table to include new values BQ24045............................ 7
• Added the Timing Requirements table..............................................................................................................10
• Deleted the last sentence in the first paragraph of the TS (BQ24040/5) section .............................................19
• Added the Section 9.2.1.3 ............................................................................................................................... 24
Changes from Revision C (February 2013) to Revision D (March 2013)
Page
• Changed Feature From: Fixed 10 Hour Safety Timer To: Fixed 10 Hour Safety Timer, BQ24040 and BQ24045
............................................................................................................................................................................1
• Changed the OUT terminal DESCRIPTION ...................................................................................................... 4
• Changed RISET NOM value in the ROC table From: 49.9 kΩ To: 10.8 kΩ..........................................................6
• Changed RISET_SHORT test conditions From: RISET : 600Ω → 250Ω To: RISET : 540Ω → 250Ω......................... 7
• Changed IOUT_CL test conditions From: RISET : 600Ω → 250Ω To: RISET : 540Ω → 250Ω................................. 7
• Deleted: Internally Set: BQ24041 from the TERMINATION section................................................................... 7
• Added BQ24040 and BQ24045 only to the BATTERY CHARGING TIMERS AND FAULT TIMERS section...10
• Changed text in the ISET section From: "maximum current between 1.1A and 1.35A" To: "maximum current
between 1.05A and 1.4A"................................................................................................................................. 18
• Changed the Timers section............................................................................................................................. 20
• Deleted: IOUT_TERM = 54mA from the Typical Application Circuit: BQ24041, with ASI and ASO conditions.....27
Changes from Revision B (June 2012) to Revision C (February 2013)
Page
• Added device BQ24045......................................................................................................................................1
• Added additional KISET information to the Electrical Characteristics table..........................................................7
• Added graph - Load Regulation........................................................................................................................ 11
• Added graph - Line Regulation......................................................................................................................... 11
Changes from Revision A (September 2009) to Revision B (June 2012)
Page
• Changed all occurrences of Li-Ion To: Li-Ion and Li-Pol..................................................................................... 1
Changes from Revision * (August 2009) to Revision A (September 2009)
Page
• Changed the status of the devices From: Product Preview To: Production Data............................................... 1
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
5 Device Comparison
PART NO.
VO(REG)
VOVP
PreTerm
ASI/ASO
TS/BAT_EN
PG
PACKAGE
BQ24040
4.20 V
6.6 V
Yes
No
TS (JEITA)
Yes
10-pin 2 × 2mm2 DFN
BQ24041
4.20 V
7.1 V
No
Yes
BAT_EN
Terminaton Disabled
Yes
10-pin 2 × 2mm2 DFN
BQ24045
4.35V
6.6V
Yes
No
TS (JEITA)
Yes
10-pin 2 × 2mm2 DFN
6 Pin Configuration and Functions
IN
1
10
OUT
ISET
2
9
TS
VSS
3
8
CHG
PRE-TE RM
4
7
ISET2
PG
5
6
NC
Th ermal
Pad
No t to scale
Figure 6-1. BQ24040 and BQ24045 DSQ Package 10-Pin WSON Top View
IN
1
10
OUT
ISET
2
9
BAT_EN
VSS
3
8
CHG
ASI
4
7
ISET2
PG
5
6
ASO
Th ermal
Pad
No t to scale
Figure 6-2. BQ24041 DSQ Package 10-Pin WSON Top View
Table 6-1. Pin Functions
PIN
DESCRIPTION
BQ24041
IN
1
1
I
Input power, connected to external DC supply (AC adapter or USB port). Expected range of bypass capacitors 1μF to
10μF, connect from IN to VSS.
OUT
10
10
O
Battery Connection. System Load may be connected. Expected range of bypass capacitors 1μF to 10μF.
PRE-TERM
4
–
I
Programs the Current Termination Threshold (5 to 50% of Iout which is set by ISET) and Sets the Pre-Charge Current to
twice the Termination Current Level.
Expected range of programming resistor is 1k to 10kΩ (2k: Ipgm/10 for term; Ipgm/5 for precharge)
ISET
2
2
I
Programs the Fast-charge current setting. External resistor from ISET to VSS defines fast charge current value. Range
is 10.8k (50mA) to 540Ω (1000mA).
ISET2
7
7
I
Programming the Input/Output Current Limit for the USB or Adaptor source:
BQ24040/5 => High = 500mAmax, Low = ISET, FLOAT = 100mAmax.
BQ24041 => High = 410mAmax, Low = ISET, FLOAT = 100mAmax.
9(1)
–
I
Temperature sense terminal connected to BQ24040/5 -10k at 25°C NTC thermistor, in the battery pack. Floating T
terminal or pulling High puts part in TTDM “Charger” Mode and disable TS monitoring, Timers and Termination. Pulling
terminal Low disables the IC. If NTC sensing is not needed, connect this terminal to VSS through an external 10 kΩ
resistor. A 250kΩ from TS to ground will prevent IC entering TTDM mode when battery with thermistor is removed.
BAT_EN
–
9
I
Charge Enable Input (active low)
VSS
3
3
–
Ground terminal
CHG
8
8
O
Low (FET on) indicates charging and Open Drain (FET off) indicates no Charging or Charge complete.
PG
5
5
O
Low (FET on) indicates the input voltage is above UVLO and the OUT (battery) voltage.
TS
4
I/O
BQ24040
BQ24045
NAME
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
Table 6-1. Pin Functions (continued)
PIN
I/O
DESCRIPTION
BQ24040
BQ24045
BQ24041
ASI
–
4
I
Auto start External input. Internal 200kΩ pull-down.
ASO
–
6
O
Auto Start Logic Output
NC
6
–
NA
Pad
2x2mm2
Pad
2x2mm2
–
NAME
Thermal Pad and
Package
(1)
Do not make a connection to this terminal (for internal use) – Do not route through this terminal
Connect exposed thermal pad to VSS terminal of the device and main ground plane. The thermal pad must be
connected to the same potential as the VSS terminal on the printed circuit board. Do not use the thermal pad as the
primary ground input for the device. VSS terminal must be connected to ground at all times.
Spins have different terminal definitions
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
7 Specifications
7.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)(1)
Input voltage
MIN
MAX
UNIT
IN (with respect to VSS)
–0.3
30
V
OUT (with respect to VSS)
–0.3
7
V
PRE-TERM, ISET, ISET2, TS, CHG, PG, ASI, ASO
(with respect to VSS)
–0.3
7
V
A
Input current
IN
1.25
Output current (continuous)
OUT
1.25
A
Output sink current
CHG
15
mA
TJ
Junction temperature
–40
150
°C
Tstg
Storage temperature
–65
150
°C
(1)
Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating
conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. All voltage
values are with respect to the network ground terminal unless otherwise noted.
7.2 ESD Ratings
VALUE
Human-body model (HBM), per ANSI/ESDA/JEDEC
V(ESD)
(1)
(2)
(3)
Electrostatic discharge(3)
JS-001(1)
UNIT
±3000
Charged-device model (CDM), per JEDEC specification JESD22-C101 or
ANSI/ESDA/JEDEC JS-002(2)
V
±1500
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
The test was performed on IC terminals that may potentially be exposed to the customer at the product level. The BQ2404x IC requires
a minimum of the listed capacitance, external to the IC, to pass the ESD test. The D+ D- lines require clamp diodes such as
CM1213A-02SR from CMD to protect the IC for this testing.
7.3 Recommended Operating Conditions
see (1)
IN voltage range
VIN
IN operating voltage range, Restricted by VDPM and VOVP
IIN
6
NOM
3.5
28
V
4.45
6.45
V
1
A
Input current, IN terminal
IOUT
Current, OUT terminal
TJ
Junction temperature
RPRE-TERM
Programs precharge and termination current thresholds
RISET
Fast-charge current programming resistor
RTS
10k NTC thermistor range without entering BAT_EN or TTDM
(1)
MIN
0
UNIT
1
A
125
°C
1
10
kΩ
0.540
10.8
kΩ
1.66
258
kΩ
Operation with VIN less than 4.5V or in drop-out may result in reduced performance.
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
7.4 Thermal Information
BQ2404x
THERMAL
METRIC(1)
UNIT
DSQ (WSON)
10 PINS
RθJA
Junction-to-ambient thermal resistance
63.5
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
79.5
°C/W
RθJB
Junction-to-board thermal resistance
33.9
°C/W
ψJT
Junction-to-top characterization parameter
7.8
°C/W
ψJB
Junction-to-board characterization parameter
34.3
°C/W
RθJC(bot)
Junction-to-case (bottom) thermal resistance
7.5
°C/W
(1)
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
7.5 Electrical Characteristics
Over junction temperature range 0°C ≤ TJ ≤ 125°C and recommended supply voltage (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
INPUT
UVLO
Undervoltage lock-out Exit
VIN: 0V → 4V Update based on sim/char
3.15
3.3
3.45
V
VHYS_UVLO
Hysteresis on VUVLO_RISE falling
VIN: 4V→0V,
VUVLO_FALL = VUVLO_RISE –VHYS-UVLO
175
227
280
mV
VIN-DT
Input power good detection threshold is VOUT (Input power good if VIN > VOUT + VIN-DT); VOUT = 3.6V,
+ VIN-DT
VIN: 3.5V → 4V
30
80
145
mV
VHYS-INDT
Hysteresis on VIN-DT falling
VIN: 5V → 12V (BQ24040, BQ24045)
6.5
6.65
6.8
VIN: 5V → 12V (BQ24041)
6.9
7.1
7.3
Feature active in USB mode; Limit Input Source Current to
50mA; VOUT= 3.5V; RISET = 825Ω
4.34
4.4
4.46
Feature active in Adaptor mode; Limit Input Source
Current to 50mA; VOUT = 3.5V; RISET = 825
4.24
4.3
4.46
VOVP
Input over-voltage protection threshold
VHYS-OVP
Hysteresis on OVP
VIN-DPM
IIN-USB-CL
VOUT = 3.6V, VIN: 4V → 3.5V
31
VIN: 11V → 5V
USB/Adaptor low input voltage protection.
Restricts lout at VIN-DPM
mV
95
V
mV
V
USB input I-Limit 100mA
ISET2 = Float; RISET = 825Ω
85
92
100
USB input I-Limit 500mA, BQ24040,
BQ24045
ISET2 = High; RISET = 825Ω
430
462
500
USB input I-Limit 380mA, BQ24041
ISET2 = High; RISET = 825Ω
350
386
420
mA
ISET SHORT CIRCUIT TEST
RISET_SHORT
Highest Resistor value considered a fault
(short). Monitored for Iout>90mA
RISET: 540Ω → 250Ω, Iout latches off. Cycle power to
Reset.
280
500
Ω
IOUT_CL
Maximum OUT current limit Regulation
(Clamp)
VIN = 5V, VOUT = 3.6V, VISET2 = Low, RISET: 540Ω →
250Ω, IOUT latches off after tDGL-SHORT
1.05
1.4
A
0.75
0.85
V
BATTERY SHORT PROTECTION
VOUT(SC)
OUT terminal short-circuit detection
threshold/ precharge threshold
VOUT: 3V → 0.5V, no deglitch
VOUT(SC-HYS)
OUT terminal Short hysteresis
Recovery ≥ VOUT(SC) + VOUT(SC-HYS);
Rising, no Deglitch
IOUT(SC)
Source current to OUT terminal during shortcircuit detection
VOUT < 0.8 V
0.8
77
10
15
mV
20
mA
QUIESCENT CURRENT
IOUT(PDWN)
Battery current into OUT terminal
VIN = 0V
1
IOUT(DONE)
OUT terminal current, charging terminated
VIN = 6V, VOUT > VOUT(REG)
6
IIN(STDBY)
Standby current into IN terminal
TS = LO, VIN ≤ 6V
Active supply current, IN terminal
TS = open, VIN = 6V, TTDM – no load on OUT terminal,
VOUT > VOUT(REG), IC enabled
ICC
0.8
μA
125
μA
1
mA
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
7.5 Electrical Characteristics (continued)
Over junction temperature range 0°C ≤ TJ ≤ 125°C and recommended supply voltage (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
VIN = 5.5V, IOUT = 25mA,
(VTS-45°C ≤ VTS ≤ VTS-0°C, BQ24040)
4.16
4.2
4.23
VIN = 5.5V, IOUT = 25mA,
(VTS-45°C ≤ VTS ≤ VTS-0°C, BQ24045)
4.30
4.35
4.40
VIN = 5.5V, IOUT = 25mA,
(VTS-45°C≤ VTS ≤ VTS-0°C, BQ24040)
4.02
4.06
4.1
VIN = 5.5V, IOUT = 25mA,
(VTS-45°C ≤ VTS ≤ VTS-0°C, BQ24045)
4.16
4.2
4.23
UNIT
BATTERY CHARGER FAST-CHARGE
VOUT(REG)
VO_HT(REG)
Battery regulation voltage
Battery hot regulation voltage
IOUT(RANGE)
Programmed Output “fast charge” current
range
VOUT(REG) > VOUT > VLOWV; VIN = 5V, ISET2 = LO, RISET =
540 to 10.8kΩ
VDO(IN-OUT)
Drop-Out, VIN – VOUT
Adjust VIN down until IOUT = 0.5A, VOUT = 4.15V, RISET =
540 , ISET2 = Lo (adaptor mode); TJ ≤ 100°C
IOUT
Output “fast charge” formula
VOUT(REG) > VOUT > VLOWV; VIN = 5V, ISET2 = Lo
KISET
Fast charge current factor
KISET
Fast charge current factor (BQ24045)
V
V
10
325
1000
mA
500
mV
KISET/RISET
A
RISET = KISET /IOUT; 50 < IOUT < 1000 mA
510
540
570
RISET = KISET /IOUT; 25 < IOUT < 50 mA
480
527
600
RISET = KISET /IOUT; 10 < IOUT < 25 mA
350
520
680
AΩ
RISET = KISET /IOUT; 50 < IOUT < 1000 mA
510
560
585
RISET = KISET /IOUT; 25 < IOUT < 50 mA
480
557
596
RISET = KISET /IOUT; 10 < IOUT < 25 mA
350
555
680
2.4
2.5
2.6
18
20
22 %IOUT-CC
AΩ
PRECHARGE – SET BY PRETERM terminal: BQ24040 / BQ24045; Internally Set: BQ24041
VLOWV
Pre-charge to fast-charge transition threshold
IPRE-TERM
See the Termination Section
%PRECHG
KPRE-CHG
Pre-charge current, default setting
VOUT < VLOWV; RISET = 1080Ω; BQ24040: RPRE-TERM=
High Z; BQ24041: Internally Fixed
Pre-charge current formula
RPRE-TERM = KPRE-CHG (Ω/%) × %PRE-CHG (%)
% Pre-charge Factor
V
RPRE-TERM/KPRE-CHG%
VOUT < VLOWV, VIN = 5V, RPRE-TERM = 2k to 10kΩ; RISET =
1080Ω , RPRE-TERM = KPRE-CHG × %IFAST-CHG, where
%IFAST-CHG is 20 to 100%
90
100
110
Ω/%
VOUT < VLOWV, VIN = 5V, RPRE-TERM = 1k to 2kΩ; RISET =
1080Ω, RPRE-TERM = KPRE-CHG × %IFAST-CHG, where
%IFAST-CHG is 10% to 20%
84
100
117
Ω/%
9
10
TERMINATION – SET BY PRE-TERM terminal: BQ24040 / BQ24045
%TERM
KTERM
Termination Threshold Current, default
setting
VOUT > VRCH; RISET = 1k; BQ24040 / BQ24045:
RPRE-TERM= High Z
Termination Current Threshold Formula,
BQ24040 / BQ24045
RPRE-TERM = KTERM (Ω/%) × %TERM (%)
% Term Factor
IPRE-TERM
Current for programming the term. and prechg with resistor. ITerm-Start is the initial PRETERM curent.
%TERM
Termination current formula
ITerm-Start
Elevated PRE-TERM current for, tTerm-Start,
during start of charge to prevent recharge of
full battery,
11 %IOUT-CC
RPRE-TERM/ KTERM
VOUT > VRCH, VIN = 5V, RPRE-TERM = 2k to 10kΩ ; RISET =
750Ω KTERM × %IFAST-CHG, where %IFAST-CHG is 10 to 50%
182
200
216
VOUT > VRCH, VIN = 5V, RPRE-TERM = 1k to 2kΩ ; RISET =
750Ω KTERM × %Iset, where %Iset is 5 to 10%
174
199
224
71
75
81
μA
Ω/%
RPRE-TERM = 2k, VOUT = 4.15V
RTERM/ KTERM %
80
85
92
μA
VO(REG)
–0.120
VO(REG)–0.095
VO(REG)–
0.070
V
VO_HT(REG)
–0.130
VO_HT(REG)
–0.105
VO_HT(REG)
–0.080
V
VO(REG)-0.450
VO(REG)-0.400
VO(REG)-350
V
RECHARGE OR REFRESH – BQ24040 / BQ24045
Recharge detection threshold – Normal Temp VIN = 5V, VTS = 0.5V, VOUT: 4.25V → VRCH
VRCH
Recharge detection threshold – Hot Temp
VIN = 5V, VTS = 0.2V, VOUT: 4.15V → VRCH
BATTERY DETECT ROUTINE – BQ24040 / BQ24045 (NOTE: In Hot mode VO(REG) becomes VO_HT(REG))
8
VREG-BD
VOUT Reduced regulation during battery
detect
IBD-SINK
Sink current during VREG-BD
VIN = 5V, VTS = 0.5V, Battery Absent
6
10
VO(REG)-0.100 VO(REG)-0.050
V
VREG-BD
+0.15
V
VBD-HI
High battery detection threshold
VIN = 5V, VTS = 0.5V, Battery Absent
VO(REG)
-0.150
VBD-LO
Low battery detection threshold
VIN = 5V, VTS = 0.5V, Battery Absent
VREG-BD
+0.50
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mA
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
7.5 Electrical Characteristics (continued)
Over junction temperature range 0°C ≤ TJ ≤ 125°C and recommended supply voltage (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
BATTERY-PACK NTC MONITOR; TS Terminal: BQ24040 / BQ24045: 10k NTC
INTC-10k
NTC bias current
VTS = 0.3V
48
50
52
μA
INTC-DIS-10k
10k NTC bias current when Charging is
disabled.
VTS = 0V
27
30
34
μA
INTC-FLDBK-10k
INTC is reduced prior to entering TTDM to
keep cold thermistor from entering TTDM
VTS: Set to 1.525V
4
5
6.5
μA
VTTDM(TS)
Termination and timer disable mode
Threshold – Enter
VTS: 0.5V → 1.7V; Timer Held in Reset
1550
1600
1650
mV
VHYS-TTDM(TS)
Hysteresis exiting TTDM
VTS: 1.7V → 0.5V; Timer Enabled
VCLAMP(TS)
TS maximum voltage clamp
VTS = Open (Float)
1800
1950
VTS_I-FLDBK
TS voltage where INTC is reduce to keep
thermistor from entering TTDM
INTC adjustment (90 to 10%; 45 to 6.6uS) takes place
near this spec threshold.
VTS: 1.425V → 1.525V
CTS
Optional Capacitance – ESD
VTS-0°C
Low temperature CHG Pending
Low Temp Charging to Pending;
VTS: 1V → 1.5V
VHYS-0°C
Hysteresis at 0°C
Charge pending to low temp charging;
VTS: 1.5V → 1V
VTS-10°C
Low temperature, half charge
Normal charging to low temp charging;
VTS: 0.5V → 1V
VHYS-10°C
Hysteresis at 10°C
Low temp charging to normal CHG;
VTS: 1V → 0.5V
VTS-45°C
High temperature at 4.1V
Normal charging to high temp CHG;
VTS: 0.5V → 0.2V
VHYS-45°C
Hysteresis at 45°C
High temp charging to normal CHG;
VTS: 0.2V → 0.5V
VTS-60°C
High temperature Disable
High temp charge to pending;
VTS: 0.2V → 0.1V
VHYS-60°C
Hysteresis at 60°C
Charge pending to high temp CHG;
VTS: 0.1V → 0.2V
VTS-EN-10k
Charge Enable Threshold, (10k NTC)
VTS: 0V → 0.175V
VTS-DIS_HYS-10k
HYS below VTS-EN-10k to Disable, (10k NTC)
VTS: 0.125V → 0V
100
1205
mV
2000
1475
mV
0.22
μF
1230
1255
86
765
790
278
815
178
293
88
mV
mV
186
11.5
80
mV
mV
10.7
170
mV
mV
35
263
mV
mV
mV
96
mV
12
mV
°C
THERMAL REGULATION
TJ(REG)
Temperature regulation limit
125
TJ(OFF)
Thermal shutdown temperature
155
°C
TJ(OFF-HYS)
Thermal shutdown hysteresis
20
°C
BAT_EN , BQ24041
IBAT_EN
Current Sourced out of terminal
VIL
Logic LOW enables charger
VIH
Logic HIGH disables charger
VCLAMP
Floating Clamp Voltage
VBAT_EN < 1.4 V
Floating BAT_EN terminal
2.3
9
μA
0
0.4
V
1.1
6
V
1.8
V
0.4
V
9
μA
1.4
5
1.6
LOGIC LIVELS ON ISET2
VIL
Logic LOW input voltage
Sink 8 μA
VIH
Logic HIGH input voltage
Source 8 μA
IIL
Sink current required for LO
VISET2 = 0.4V
IIH
Source current required for HI
VISET2 = 1.4V
VFLT
ISET2 Float Voltage
1.4
V
2
1.1
575
900
9.5
μA
1225
mV
AUTO START, ASI AND ASO TERMINALS, BQ24041
VASIL
Has 200k Internal Pull-down
0.4
VASIH
1.3
VASOL
Auto Start Output Sinks 1mA
VASOH
Auto Start Input Sources 1mA
V
V
0.4
VOUT - 0.4
V
V
LOGIC LEVELS ON CHG AND PG
VOL
Output LOW voltage
ISINK = 5 mA
ILEAK
Leakage current into IC
V CHG = 5V, V PG = 5V
0.4
V
1
µA
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
7.6 Timing Requirements
MIN
NOM
MAX
UNIT
INPUT
tDGL(PG_PWR)
Deglitch time on exiting sleep.
Time measured from VIN: 0V → 5V 1μs rise-time to
PG = low, VOUT = 3.6V
45
μs
tDGL(PG_NO-
Deglitch time on VHYS-INDT power down.
Same as entering sleep.
Time measured from VIN: 5V → 3.2V 1μs fall-time to
PG = OC, VOUT = 3.6V
29
ms
PWR)
tDGL(OVP-SET)
Input over-voltage blanking time
VIN: 5V → 12V
113
μs
tDGL(OVP-REC)
Deglitch time exiting OVP
Time measured from VIN: 12V → 5V 1μs fall-time to
PG = LO
30
μs
Clear fault by disconnecting IN or cycling (high / low)
TS/ BAT_EN
1
ms
ISET SHORT CIRCUIT TEST
tDGL_SHORT
Deglitch time transition from ISET short to
IOUT disable
PRECHARGE – SET BY PRETERM PIN: BQ24040 / BQ24045; Internally Set: BQ24041
tDGL1(LOWV)
Deglitch time on pre-charge to fast-charge
transition
70
μs
tDGL2(LOWV)
Deglitch time on fast-charge to pre-charge
transition
32
ms
TERMINATION – SET BY PRE-TERM PIN: BQ24040 / BQ24045
tDGL(TERM)
Deglitch time, termination detected
tTerm-Start
Elevated termination threshold initially
active for tTerm-Start
29
ms
1.25
min
RECHARGE OR REFRESH – BQ24040 / BQ24045
tDGL1(RCH)
Deglitch time, recharge threshold detected VIN = 5V, VTS = 0.5V, VOUT: 4.25V → 3.5V in 1μs;
tDGL(RCH) is time to ISET ramp
29
ms
tDGL2(RCH)
Deglitch time, recharge threshold detected VIN = 5V, VTS = 0.5V, VOUT = 3.5V inserted; tDGL(RCH)
in OUT-Detect Mode
is time to ISET ramp
3.6
ms
25
ms
BATTERY DETECT ROUTINE – BQ24040 / BQ24045 (NOTE: In Hot mode VO(REG) becomes VO_HT(REG))
tDGL(HI/LOW
Regulation time at VREG or VREG-BD
REG)
BATTERY CHARGING TIMERS AND FAULT TIMERS: BQ24040 and BQ24045 only
tPRECHG
Pre-charge safety timer value
Restarts when entering Pre-charge; Always enabled
when in pre-charge.
1700
1940
2250
s
tMAXCH
Charge safety timer value
Clears fault or resets at UVLO, TS/ BAT_EN disable,
OUT Short, exiting LOWV and Refresh
34000
38800
45000
s
BATTERY-PACK NTC MONITOR; TS Terminal: BQ24040 / BQ24045: 10k NTC
tDGL(TTDM)
Deglitch exit TTDM between states
57
Deglitch enter TTDM between states
tDGL(TS_10C)
Deglitch for TS thresholds: 10C.
tDGL(TS)
Deglitch for TS thresholds: 0/45/60C.
10
ms
8
μs
Normal to Cold Operation; VTS: 0.6V → 1V
50
ms
Cold to Normal Operation; VTS: 1V → 0.6V
12
ms
Battery charging
30
ms
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
7.7 Typical Operational Characteristics (Protection Circuits Waveforms)
SETUP: BQ24040 typical applications schematic; VIN = 5V, VBAT = 3.6V (unless otherwise indicated)
4.212
546
VO at 0°C
Kiset
VOUT - Output Voltage DC - V
542
Low to High Currents
(may occur in recharge to fast charge transion)
540
Kiset - W
ROUT = 100 Ω
4.21
544
538
High to Low Currents
(may occur in Voltage Regulation - Taper Current)
536
534
532
4.208
4.206
VO at 25°C
4.204
VO at 85°C
4.202
4.2
4.198
530
4.196
4.5
528
.15
0
0.2
0.4
IO - Output Current - A
0.6
0.8
5
5.5
VI - Input Voltage DC - V
6
6.5
Figure 7-2. Line Regulation
Figure 7-1. Kiset for Low and High Currents
4.2
4.352
VREG at 0°C
4.199
4.35
4.198
VREG - Voltage - V
VOUT - Output Voltage - V
Vreg at 25°C
Vreg at 85°C
4.197
4.196
4.195
Vreg at 0°C
VREG at 25°C
4.348
VREG at 85°C
4.346
VREG at 125°C
4.344
4.194
4.342
4.193
4.34
4.192
0
0.2
0.4
0.6
IO - Output current - A
0.8
0
1
300
400
500
600
700
800
900
Figure 7-4. Load Regulation
363.4
4.3450
363.2
4.3445
IO at 25°C
VREG at 0°C
IO - Output Current - mA
VOUT - Output Voltage - V
200
ILOAD - Current - mA
Figure 7-3. Load Regulation Over Temperature
4.3440
4.3435
VREG at 25°C
4.3430
4.3425
363
362.8
4.3420
IO at 85°C
362.6
362.4
362.2
VREG at 85°C
4.3415
4.5
100
IO at 0°C
362
5
5.5
6
6.5
7
361.8
2.5
3
VIN - Input Voltage - V
Figure 7-5. Line Regulation
3.5
VO - Output Voltage - V
4
4.5
Figure 7-6. Current Regulation Over Temperature
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8 Detailed Description
8.1 Overview
The BQ2404x is a highly integrated family of 2×2 single cell Li-Ion and Li-Pol chargers. The charger can be used
to charge a battery, power a system or both. The charger has three phases of charging: Pre-charge to recover a
fully discharged battery, fast-charge constant current to supply the buck charge safely and voltage regulation to
safely reach full capacity. The charger is very flexible, allowing programming of the fast-charge current and Precharge/Termination Current (BQ24040/5 only). This charger is designed to work with a USB connection or
Adaptor (DC out). The charger also checks to see if a battery is present.
The charger also comes with a full set of safety features: JEITA Temperature Standard (BQ24040/5 only), OverVoltage Protection, DPM-IN, Safety Timers, and ISET short protection. All of these features and more are
described in detail below.
The charger is designed for a single power path from the input to the output to charge a single cell Li-Ion or
Li-Pol battery pack. Upon application of a 5VDC power source the ISET and OUT short checks are performed to
assure a proper charge cycle.
If the battery voltage is below the LOWV threshold, the battery is considered discharged and a preconditioning
cycle begins. The amount of precharge current can be programmed using the PRE-TERM terminal which
programs a percent of fast charge current (10 to 100%) as the precharge current. This feature is useful when the
system load is connected across the battery “stealing” the battery current. The precharge current can be set
higher to account for the system loading while allowing the battery to be properly conditioned. The PRE-TERM
terminal is a dual function terminal which sets the precharge current level and the termination threshold level.
The termination "current threshold" is always half of the precharge programmed current level.
Once the battery voltage has charged to the VLOWV threshold, fast charge is initiated and the fast charge
current is applied. The fast charge constant current is programmed using the ISET terminal. The constant
current provides the bulk of the charge. Power dissipation in the IC is greatest in fast charge with a lower battery
voltage. If the IC reaches 125°C the IC enters thermal requlation, slows the timer clock by half and reduce the
charge current as needed to keep the temperature from rising any further. Figure 8-1 shows the charging profile
with thermal regulation. Typically under normal operating conditions, the IC’s junction temperature is less than
125°C and thermal regulation is not entered.
Once the cell has charged to the regulation voltage the voltage loop takes control and holds the battery at the
regulation voltage until the current tapers to the termination threshold. The termination can be disabled if
desired. The CHG terminal is low (LED on) during the first charge cycle only and turns off once the termination
threshold is reached, regardless if termination, for charge current, is enabled or disabled.
Further details are mentioned in the Operating Modes section.
12
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
8.2 Functional Block Diagram
Internal Charge
Current Sense
w/ Multiple Outputs
IN
OUT
80 mV
+
_
OUT
Input
Power
Detect
IN
OUT
+
_
+
_
+
-
IN-DPMREF
Charge
Pump
IOUT x 1.5 V
540 AW
OUTREGREF
TJ°C
+
_
FAST CHARGE
125°CREF
PRE-CHARGE
ISET
IN
+
_
1.5V
Pre-CHG Reference
TJoC
+
_
+
_
Term Reference
o
150 CREF
Thermal Shutdown
+
X2 Gain (1: 2)
Term:Pre-CHGX2
PRE-TERM
+
BQ24040 and
BQ24045 Only
Increased from 75mA to 85mA for
1st minute of charge.
IN
CHG
OVPREF
+
_
OUT
VTERM_EN
Charge
Pump
+
_
75mA
+
_
USB100/500REF
USB Sense
Resistor
+
_
ON:
OFF:
ISET2 (LO = ISET, HI = USB500,
0.9V Float
On During
1st Charge Only
CHARGE
CONTROL
FLOAT = USB100)
PG
VCOLD-10 C
o
+
_
o
+
_
VHOT-45 C
HI = Half CHG (JEITA)
HI = 4.06Vreg (JEITA)
OUT
VCOLD-FLT
ASO
+
_
BQ24041
Only
ASI
+
_
VHOT-FLT
LO = TTDM MODE
HI = Suspend CHG
200kW
TS/BAT_EN
VTTDM
TS - BQ24040 and
BQ24045
BAT_EN - bq24041
VCE
+
_
+
_
BQ24041 This Comparator Only – No TS Features
HI=CHIP DISABLE
VDISABLE
+
_
Cold Temperature
Sink Current
VCLAMP = 1.4V
= 45mA
+
_
5 mA
Disable
Sink Current
= 20mA
+
_
45mA
BQ24040 and BQ24045 are as shown
BQ24041 has no Current Sinks and only 5mA Current Source
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
8.3 Feature Description
VO(REG)
PreConditioning
Phase
Thermal
Regulation
Phase
Current
Regulation
Phase
Voltage Regulation and
Charge Termination
Phase
DONE
IO(OUT)
FAST-CHARGE
CURRENT
PRE-CHARGE
CURRENT AND
TERMINATION
THRESHOLD
Battery
Voltage,
V(OUT)
Battery Current,
I(OUT)
Charge
Complete
Status,
Charger
Off
VO(LOWV)
I(TERM)
IO(PRECHG)
T(THREG)
0A
Temperature, Tj
T(PRECHG)
T(CHG)
DONE
Figure 8-1. Charging Profile With Thermal Regulation
8.3.1 Power-Down or Undervoltage Lockout (UVLO)
The BQ2404x family is in power down mode if the IN terminal voltage is less than UVLO. The part is considered
“dead” and all the terminals are high impedance. Once the IN voltage rises above the UVLO threshold the IC will
enter Sleep Mode or Active mode depending on the OUT terminal (battery) voltage.
8.3.2 Power-up
The IC is alive after the IN voltage ramps above UVLO (see sleep mode), resets all logic and timers, and starts
to perform many of the continuous monitoring routines. Typically the input voltage quickly rises through the
UVLO and sleep states where the IC declares power good, starts the qualification charge at 100mA, sets the
input current limit threshold base on the ISET2 terminal, starts the safety timer and enables the CHG terminal.
See Figure 8-2.
8.3.3 Sleep Mode
If the IN terminal voltage is between than VOUT+VDT and UVLO, the charge current is disabled, the safety timer
counting stops (not reset) and the PG and CHG terminals are high impedance. As the input voltage rises and the
charger exits sleep mode, the PG terminal goes low, the safety timer continues to count, charge is enabled and
the CHG terminal returns to its previous state. See Figure 8-3.
8.3.4 New Charge Cycle
A new charge cycle is started when any of these events occur:
• A valid power source is applied;
• The chip is enabled/disabled using TS pin or BAT_EN;
• Exit of termination/Timer Disable Mode (TTDM);
• Detection of batter insertion;
• OUT voltage drops below the VRCH threshold.
The CHG signal is active only during the first charge cycle. Exiting TTDM or the OUT voltage falling below VRCH
will not activate the CHG signal if it is already in the open-drain (off) state.
14
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VSS
1.8V
Disabled
4.06 V
HOT
Operation
Normal
Operation
4.06 V
HOT
Operation
HOT
Fault
Disabled
Normal
Operation
Cold
Operation
Cold
Fault
LDO
Mode
Cold
Fault
tDGL(TTDM)
Enter
Normal
Operation
Cold
Operation
t < tDGL(IS)
Normal
Operation
LDO
Mode
tDGL(TTDM)
Enter
tDGL(TTDM)
Exit
LDO
t < tDGL(TTDM)
Exit
LDOHYS
tDGL(TS)
tDGL(TS)
tDGL(TS1_IOC)
Cold to Normal
0°C
0°CHYS
tDGL(TS_IOC)
Rising
tDGL(TS_IOC)
Falling
10°C
10°CHYS
tDGL(TS)
tDGL(TS)
tDGL(TS)
45°CHYS
45°C
tDGL(TS)
tDGL(TS)
60°CHYS
Dots Show Threshold Trip Points
fllowed by a deglitch time before
transitioning into a new mode.
60°C
EN
DISHYS
0V
t
Drawing Not to Scale
Figure 8-2. TS Battery Temperature Bias Threshold and Deglitch Timers
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
Apply Input
Power
Is power good?
VBAT +VDT < VIN < VOVP
& VUVLO < VIN
No
Turn on PG FET
PG pin LOW
Yes
Is chip enabled?
VTS > VEN
No
Yes
Set Input Current Limit to 100 mA
and Start Charge
Perform ISET & OUT short tests
Remember ISET2 State
Set charge current
based on ISET2 truth
table.
Return to
Charge
Figure 8-3. BQ2404x Power-Up Flow Diagram
8.3.5 Overvoltage-Protection (OVP) – Continuously Monitored
If the input source applies an overvoltage, the pass FET, if previously on, turns off after a deglitch, tBLK(OVP). The
timer ends and the CHG and PG terminal goes to a high impedance state. Once the overvoltage returns to a
normal voltage, the PG terminal goes low, timer continues, charge continues and the CHG terminal goes low
after a 25ms deglitch. PG terminal is optional on some packages
8.3.6 Power Good Indication ( PG)
After application of a 5V source, the input voltage rises above the UVLO and sleep thresholds (VIN>VBAT+VDT),
but is less than OVP (VINVBAT +
VIN-DT) and an external input from ASI terminal (internal 100kΩ pull-down). The ASO terminal outputs a signal
that can be used as a system boot signal. The OR gate is powered by the OUT terminal and the OUT terminal
must be powered by an external source (battery or P/S) or via the IN terminal for the ASO terminal to deliver a
logic High. The ASI and/or the internal power good signal have to be logic high for the ASO to be logic high. The
ASI/ASO, OUT and PG signals are used in production testing to test the system without a battery.
8.4.3 IN-DPM (VIN-DPM or IN-DPM)
The IN-DPM feature is used to detect an input source voltage that is folding back (voltage dropping), reaching its
current limit due to excessive load. When the input voltage drops to the VIN-DPM threshold the internal pass FET
starts to reduce the current until there is no further drop in voltage at the input. This would prevent a source with
voltage less than VIN-DPM to power the out terminal. This works well with current limited adaptors and USB ports
as long as the nominal voltage is above 4.3V and 4.4V respectively. This is an added safety feature that helps
protect the source from excessive loads.
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8.4.4 OUT
The Charger’s OUT terminal provides current to the battery and to the system, if present. This IC can be used to
charge the battery plus power the system, charge just the battery or just power the system (TTDM) assuming the
loads do not exceed the available current. The OUT terminal is a current limited source and is inherently
protected against shorts. If the system load ever exceeds the output programmed current threshold, the output
will be discharged unless there is sufficient capacitance or a charged battery present to supplement the
excessive load.
8.4.5 ISET
An external resistor is used to Program the Output Current (50 to 1000mA) and can be used as a current
monitor.
RISET = KISET / IOUT
(1)
where
•
•
IOUT is the desired fast charge current;
KISET is a gain factor found in the electrical specification
For greater accuracy at lower currents, part of the sense FET is disabled to give better resolution. Figure 7-1
shows the transition from low current to higher current. Going from higher currents to low currents, there is
hysteresis and the transition occurs around 0.15A.
o
1.8
For < 45 C, 4.2V Regulation
No Operation
During Cold
Fault
3.5
o
60 C to 45 C
HOT TEMP
4.06V
Regulation
3
1.6
o
1.4
VOUT
IO - Output Current - A
Normalized OUT Current and VREG - V
4
2.5
< 48oC
1.5
o
o
o
0C
10 C
60 C
Termination
Disable
2
0.5
0
0
} IC Disable
} Hot Fault
100% of Programmed
Current
1
0.4
0.6
0.8
1
1.2
1.4
IOUT Internal Clamp Range
1
0.8
IOUT Programmed
max
0.6
ISET Short
Fault
Range
min
0.2
Cold
Fault
IOUT
0.2
1.2
0.4
50%
IOUT Clamp min - max
4.5
IOUT Fault min - max
The ISET resistor is short protected and will detect a resistance lower than ≉340Ω. The detection requires at
least 80mA of output current. If a “short” is detected, then the IC will latch off and can only be reset by cycling the
power. The OUT current is internally clamped to a maximum current between 1.05A and 1.4A and is
independent of the ISET short detection circuitry, as shown in Figure 8-5. Also, see Figure 9-14 and Figure 9-15.
Non Restricted
Operating Area
0
1.6
1.8
100
VTS - Voltage - V
Figure 8-4. Operation Over TS Bias Voltage
(BQ24040)
1000
10000
ISET - W
Figure 8-5. Programmed/Clamped Out Current
(BQ24040)
8.4.6 PRE_TERM – Pre-Charge and Termination Programmable Threshold, BQ24040/5
Pre-Term is used to program both the pre-charge current and the termination current threshold. The pre-charge
current level is a factor of two higher than the termination current level. The termination can be set between 5
and 50% of the programmed output current level set by ISET. If left floating the termination and pre-charge are
set internally at 10/20% respectively. The pre-charge-to-fast-charge, Vlowv threshold is set to 2.5V.
RPRE-TERM = %Term × KTERM = %Pre-CHG × KPRE-CHG
(2)
where
18
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•
•
•
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%Term is the percent of fast charge current where termination occurs;
%Pre-CHG is the percent of fast charge current that is desired during precharge;
KTERM and KPRE-CHG are gain factors found in the electrical specifications.
8.4.7 ISET2
ISET2 is a 3-state input and programs the Input Current Limit/Regulation Threshold. A low will program a
regulated fast charge current via the ISET resistor and is the maximum allowed input/output current for any
ISET2 setting, Float will program a 100mA Current limit and High will program a 500mA Current limit.
Below are two configurations for driving the 3-state ISET2 terminal:
VCC
VCC
To
ISET2
R1
To ISET2
Drive
Logic
Q1
OR
Drive
Logic
R1 Divider
set to 0.9 V
Which is the
Float Voltage
R2
Q2
Figure 8-6. 3-State ISET2 Terminal Circuits
8.4.8 TS (BQ24040/5)
The TS function for the BQ24040/5 is designed to follow the new JEITA temperature standard for Li-Ion and LiPol batteries. There are now four thresholds, 60°C, 45°C, 10°C, and 0°C. Normal operation occurs between
10°C and 45°C. If between 0°C and 10°C the charge current level is cut in half and if between 45°C and 60°C
the regulation voltage is reduced to 4.1Vmax, see Figure 8-4.
The TS feature is implemented using an internal 50μA current source to bias the thermistor (designed for use
with a 10k NTC β = 3370 (SEMITEC 103AT-2 or Mitsubishi TH05-3H103F) connected from the TS terminal to
VSS. If this feature is not needed, a fixed 10kΩ can be placed between TS and VSS to allow normal operation.
This may be done if the host is monitoring the thermistor and then the host would determine when to pull the TS
terminal low to disable charge.
The TS terminal has two additional features, when the TS terminal is pulled low or floated/driven high. A low
disables charge (similar to a high on the BAT_EN feature) and a high puts the charger in TTDM.
Above 60°C or below 0°C the charge is disabled. Once the thermistor reaches ≉–10°C the TS current folds back
to keep a cold thermistor (between –10°C and –50°C) from placing the IC in the TTDM mode. If the TS terminal
is pulled low into disable mode, the current is reduce to ≉30μA, see Figure 8-2. Since the ITS curent is fixed
along with the temperature thresholds, it is not possible to use thermistor values other than the 10k NTC (at
25°C).
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8.4.9 Termination and Timer Disable Mode (TTDM) - TS Terminal High
The battery charger is in TTDM when the TS terminal goes high from removing the thermistor (removing battery
pack/floating the TS terminal) or by pulling the TS terminal up to the TTDM threshold.
When entering TTDM, the 10 hour safety timer is held in reset and termination is disabled. A battery detect
routine is run to see if the battery was removed or not. If the battery was removed then the CHG terminal will go
to its high impedance state if not already there. If a battery is detected the CHG terminal does not change states
until the current tapers to the termination threshold, where the CHG terminal goes to its high impedance state if
not already there (the regulated output will remain on).
The charging profile does not change (still has pre-charge, fast-charge constant current and constant voltage
modes). This implies the battery is still charged safely and the current is allowed to taper to zero.
When coming out of TTDM, the battery detect routine is run and if a battery is detected, then a new charge cycle
begins and the CHG LED turns on.
If TTDM is not desired upon removing the battery with the thermistor, one can add a 237k resistor between TS
and VSS to disable TTDM. This keeps the current source from driving the TS terminal into TTDM. This creates
≉0.1°C error at hot and a ≉3°C error at cold.
8.4.10 Timers, BQ24040 and BQ24045 only
The pre-charge timer is set to 30 minutes. The pre-charge current, can be programmed to off-set any system
load, making sure that the 30 minutes is adequate. The BQ24041 does not have a safety timer.
The fast charge timer is fixed at 10 hours and can be increased real time by going into thermal regulation, INDPM or if in USB current limit. The timer clock slows by a factor of 2, resulting in a clock than counts half as fast
when in these modes. If either the 30 minute or ten hour timer times out, the charging is terminated and the CHG
terminal goes high impedance if not already in that state. The timer is reset by disabling the IC, cycling power or
going into and out of TTDM.
8.4.11 Termination
Once the OUT terminal goes above VRCH, (reaches voltage regulation) and the current tapers down to the
termination threshold, the CHG terminal goes high impedance and a battery detect route is run to determine if
the battery was removed or the battery is full. If the battery is present, the charge current will terminate. If the
battery was removed along with the thermistor, then the TS terminal is driven high and the charge enters TTDM.
If the battery was removed and the TS terminal is held in the active region, then the battery detect routine will
continue until a battery is inserted.
8.4.12 Battery Detect Routine
The battery detect routine should check for a missing battery while keeping the OUT terminal at a useable
voltage. Whenever the battery is missing the CHG terminal should be high impedance.
The battery detect routine is run when entering and exiting TTDM to verify if battery is present, or run all the time
if battery is missing and not in TTDM. On power-up, if battery voltage is greater than VRCH threshold, a battery
detect routine is run to determine if a battery is present.
The battery detect routine is disabled while the IC is in TTDM, or has a TS fault. See Figure 8-7 for the Battery
Detect Flow Diagram.
8.4.13 Refresh Threshold
After termination, if the OUT terminal voltage drops to VRCH (100mV below regulation) then a new charge is
initiated, but the CHG terminal remains at a high impedance (off).
8.4.14 Starting a Charge on a Full Battery
The termination threshold is raised by ≉14%, for the first minute of a charge cycle so if a full battery is removed
and reinserted or a new charge cycle is initiated, that the new charge terminates (less than 1 minute). Batteries
that have relaxed many hours may take several minutes to taper to the termination threshold and terminate
charge.
20
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Start
BATT_DETECT
Start 25ms timer
Timer Expired?
No
Yes
Is VOUTVREG-300mV?
Battery Present
Turn off Sink Current
Return to flow
No
Battery Absent
Don’t Signal Charge
Turn off Sink Current
Return to Flow
Figure 8-7. Battery Detect Routine (BQ24040)
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9 Application and Implementation
Note
Information in the following applications sections is not part of the TI component specification, and TI
does not warrant its accuracy or completeness. TI’s customers are responsible for determining
suitability of components for their purposes. Customers should validate and test their design
implementation to confirm system functionality.
9.1 Application Information
The BQ2404x series of devices are highly integrated Li-Ion and Li-Pol linear chargers devices targeted at spacelimited portable applications. The devices operate from either a USB port or AC adapter. The high input voltage
range with input overvoltage protection supports low-cost unregulated adapters. These devices have a single
power output that charges the battery. A system load can be placed in parallel with the battery as long as the
average system load does not keep the battery from charging fully during the 10 hour safety timer.
9.2 Typical Applications
9.2.1 Typical Application: BQ24040 and BQ24045
IOUT_FAST_CHG = 540mA; IOUT_PRE_CHG = 108mA; IOUT_TERM = 54mA
1.5kW
BQ24040 and BQ24045
Adaptor
1 IN
DC+
OUT 10
1.5kW
GND
1mF
1kW
2 ISET
TS 9
3 VSS
CHG 8
System Load
Battery Pack
++
1mF
4 PRETERM ISET2 7
OR
5 PG
NC 6
VDD
2kW
TTDM/BAT_EN
USB Port
ISET/100/500 mA
VBUS
GND
GND
D+
D+
D-
D-
Host
Figure 9-1. Typical Application Circuit: BQ24040 and BQ24045
9.2.1.1 Design Requirements
•
•
•
•
•
22
Supply voltage = 5 V
Fast charge current: IOUT-FC = 540 mA; ISET-terminal 2
Termination Current Threshold: %IOUT-FC = 10% of Fast Charge or about 54mA
Pre-Charge Current by default is twice the termination Current or about 108mA
TS – Battery Temperature Sense = 10k NTC (103AT)
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9.2.1.2 Detailed Design Procedure
9.2.1.2.1 Calculations
For additional information on calculations, refer to BQ24040 Application Report.
9.2.1.2.1.1 Program the Fast Charge Current, ISET:
RISET = [K(ISET) / I(OUT)]
(3)
From Section 7.5:
• K(SET) = 540AΩ
• RISET = [540AΩ/0.54A] = 1.0 kΩ
Selecting the closest standard value, use a 1.0 kΩ resistor between ISET (terminal 16) and VSS.
9.2.1.2.1.2 Program the Termination Current Threshold, ITERM:
RPRE-TERM = K(TERM) × %IOUT-FC
(4)
RPRE-TERM = 200Ω/% × 10% = 2kΩ
(5)
Selecting the closest standard value, use a 2 kΩ resistor between ITERM (terminal 15) and VSS.
One can arrive at the same value by using 20% for a pre-charge value (factor of 2 difference).
RPRE-TERM = K(PRE-CHG) × %IOUT-FC
(6)
RPRE-TERM = 100Ω/% × 20%= 2kΩ
(7)
9.2.1.2.1.3 TS Function (BQ24040)
Use a 10k NTC thermistor in the battery pack (103AT).
To Disable the temp sense function, use a fixed 10k resistor between the TS (terminal 1) and VSS.
9.2.1.2.1.4 CHG and PG
LED Status: connect a 1.5k resistor in series with a LED between the OUT terminal and the CHG terminal.
Connect a 1.5k resistor in series with a LED between the OUT terminal and the and PG terminal.
Processor Monitoring: Connect a pull-up resistor between the processor’s power rail and the CHG terminal.
Connect a pull-up resistor between the processor’s power rail and the PG terminal.
9.2.1.2.2 Selecting In and Out Terminal Capacitors
In most applications, all that is needed is a high-frequency decoupling capacitor (ceramic) on the power terminal,
input and output terminals. Using the values shown on the application diagram, is recommended. After
evaluation of these voltage signals with real system operational conditions, one can determine if capacitance
values can be adjusted toward the minimum recommended values (DC load application) or higher values for fast
high amplitude pulsed load applications. Note if designed for high input voltage sources (bad adaptors or wrong
adaptors), the capacitor needs to be rated appropriately. Ceramic capacitors are tested to 2x their rated values
so a 16V capacitor may be adequate for a 30V transient (verify tested rating with capacitor manufacturer).
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9.2.1.3 Application Curves
SETUP: BQ24040 typical applications schematic; VIN = 5V, VBAT = 3.6V (unless otherwise indicated)
Vin
Vin
5V/div
5V/div
Vout
Vout
5V/div
Vpg
5V/div
5V/div
Vpg
5V/div
Vaso
Vaso
5V/div
5V/div
t - time - 10ms/div
t - time - 10ms/div
Figure 9-2. Power-up Timing
Figure 9-3. Power-up Timing – No Battery or Load
Vasi
Vasi
5V/div
5V/div
Vout
5V/div
Vout
Vpg
Vpg
5V/div
5V/div
5V/div
Vaso
Vas
5V/div
5V/div
t - time - 20ms/div
t - time - 50ms/div
Figure 9-4. – ASI and OUT Power-up Timing – No
Input
Figure 9-5. ASI and delayed OUT Power-up Timing
– No Input
Vin
Vin
5V/div
5V/div
Vchg
2V/div
Vchg
Vpg
2V/div
Vpg
Viset
2V/div
Viset 2V/div
2V/div
t - time - 20ms/div
t - time - 100ms/div
Figure 9-6. OVP 8V Adaptor - Hot Plug
24
2V/div
Figure 9-7. OVP from Normal Power-up Operation
– VIN 0V → 5V → 8V →5V
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Vpg
Vpg
2V/div
5V/div
Vchg
Vchg
2V/div
2V/div
Vout
2V/div
500mV/div
Vts
Battery Detect Mode
Viset
Vin
2V/div
5V/div
t - time - 50ms/div
t - time - 20ms/div
10kΩ resistor from TS to GND. 10kΩ is
shorted to disable the IC
Figure 9-9. Hot Plug Source w/No Battery – Battery
Detection
.
Figure 9-8. TS Enable and Disable
Vout
Vin
1 Battery Detect Cycle
2V/div
Vchg
Vout
Viset
500mV/div
1V/div
5V/div
1V/div
Viset
1V/div
Vts
1V/div
Vts
2V/div
Entered TTDM
t - time - 5ms/div
Figure 9-10. Battery Removal – GND Removed 1st,
42 Ω Load
Vout
t - time - 10ms/div
Figure 9-11. Battery Removal with OUT and TS
Disconnect 1st, With 100 Ω Load
1V/div
1V/div
Vout
Vchg
Vchg
Battery Declared Absent
5V/div
5V/div
Viset
Viset
1V/div
Battery
Threshold
Reached
1V/div
V_0.1 W_OUT
V_0.1 W_OUT
100mV/div
100mV/div
t - time - 500ms/div
t - time - 20ms/div
Continuous battery detection when not in TTDM
CH4: IOUT (1A/Div)
Battery voltage swept from 0V to 4.25V to 3.9V.
Figure 9-12. Battery Removal with fixed TS = 0.5V
Figure 9-13. Battery Charge Profile
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Vchg
Vout
2V/div
1V/div
Vin
Vchg 2V/div
2V/div
500mV/div
Short Detected in 100mA
mode and Latched Off
IOUT Clamped Current
Viset
V_0.1 W_OUT
100mV/div
Viset
500mV/div
20mV/div
ISET Short Detected
and Latched Off
V_0.1 W_OUT
t - time - 5ms/div
t - time - 200ms/div
CH4: IOUT (0.2A/Div)
CH4: IOUT (1A/Div)
Figure 9-14. ISET Shorted During Normal
Operation
Figure 9-15. ISET Shorted Prior to USB Power-up
Vin
Vin
2V/div
Vchg
2V/div
Vchg
2V/div
2V/div
500mV/div
Viset
V_0.1W_OUT
20mV/div
500mV/div
Viset
20mV/div
V_0.1W_OUT
t - time - 1ms/div
t - time - 500ms/div
CH4: IOUT (0.2A/Div)
Figure 9-17. DPM – USB Current Limits – Vin
Regulated to 4.4V
Figure 9-16. DPM – Adaptor Current Limits – Vin
Regulated
Vin
Vout
2V/div
1V/div
Enters
Thermal
Regulation
Exits
Thermal
Regulation
Vin
Viset
1V/div
Viset
1V/div
V_0.1W_OUT
1V/div
Vchg
5V/div
Vpg
50mV/div
5V/div
t - time - 1s/div
The IC temperature rises to 125°C and enters thermal
regulation. Charge current is reduced to regulate the IC at
125°C. VIN is reduced, the IC temperature drops, the charge
current returns to the programmed value
t - time - 20ms/div
VIN swept from 5V to 3.9V to 5V
VBAT = 4V
Figure 9-19. Entering and Exiting Sleep mode
.
Figure 9-18. Thermal Reg. – Vin increases PWR/
Iout Reduced
26
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9.2.2 Typical Application Circuit: BQ24041, with ASI and ASO
IOUT_FAST_CHG = 540mA; IOUT_PRE_CHG = 108mA
1.5kW
BQ24041
Adaptor
1 IN
DC+
OUT 10
System Load
1.5kW
GND
2 ISET
BAT_EN 9
3 VSS
CHG 8
Battery Pack
1kW
++
1mF
OR
4
Auto-Booting
ASI
ISET2 7
5 PG
ASO 6
1mF
TTDM/BAT_EN
USB Port
ISET/100/500 mA
VBUS
GND
GND
D+
D+
D-
D-
VDD
Host
EN
Power Supply
Figure 9-20. Typical Application Circuit: BQ24041, with ASI and ASO
9.2.2.1 Design Requirements
See Section 9.2.1 for design requirements.
9.2.2.2 Detailed Design Procedure
See Section 9.2.1 for detailed design procedures.
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9.2.2.3 Application Curves
SETUP: BQ24041 typical applications schematic; VIN = 5V, VBAT = 3.6V (unless otherwise indicated)
Vin
Vin
5V/div
5V/div
Vout
Vout
5V/div
Vpg
5V/div
5V/div
Vpg
5V/div
Vaso
Vaso
5V/div
5V/div
t - time - 10ms/div
t - time - 10ms/div
Figure 9-21. Power-up Timing, BQ24041
Figure 9-22. Power-up Timing – No Battery or
Load, BQ24041
Vasi
Vasi
5V/div
5V/div
Vout
5V/div
Vout
Vpg
Vpg
5V/div
5V/div
5V/div
Vaso
Vas
5V/div
5V/div
28
t - time - 20ms/div
t - time - 50ms/div
Figure 9-23. – ASI and OUT Power-up Timing – No
Input, BQ24041
Figure 9-24. ASI and Delayed OUT Power-up
Timing – No Input, BQ24041
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10 Power Supply Recommendations
The devices are designed to operate from an input voltage supply range between 3.5 V and 28 V and current
capability of at least the maximum designed charge current. This input supply should be well regulated. If located
more than a few inches from the BQ24040x IN and GND terminals, a larger capacitor is recommended.
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11 Layout
11.1 Layout Guidelines
To obtain optimal performance, the decoupling capacitor from IN to GND (thermal pad) and the output filter
capacitors from OUT to GND (thermal pad) should be placed as close as possible to the BQ2405x, with short
trace runs to both IN, OUT, and GND (thermal pad).
•
•
•
All low-current GND connections should be kept separate from the high-current charge or discharge paths
from the battery. Use a single-point ground technique incorporating both the small signal ground path and the
power ground path.
The high current charge paths into IN terminal and from the OUT terminal must be sized appropriately for the
maximum charge current in order to avoid voltage drops in these traces
The BQ2404x family is packaged in a thermally enhanced MLP package. The package includes a thermal
pad to provide an effective thermal contact between the IC and the printed circuit board (PCB); this thermal
pad is also the main ground connection for the device. Connect the thermal pad to the PCB ground
connection. It is best to use multiple 10mil vias in the power pad of the IC and close enough to conduct the
heat to the bottom ground plane. The bottom ground plane should avoid traces that “cut off” the thermal path.
The thinner the PCB the less temperature rise. The EVM PCB has a thickness of 0.031 inches and uses 2 oz.
(2.8mil thick) copper on top and bottom, and is a good example of optimal thermal performance.
11.2 Layout Example
Figure 11-1. Board Layout
30
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11.3 Thermal Considerations
The BQ2404x family is packaged in a thermally enhanced MLP package. The package includes a thermal pad to
provide an effective thermal contact between the IC and the printed circuit board (PCB). The power pad should
be directly connected to the VSS terminal. Full PCB design guidelines for this package are provided in the
application note entitled: QFN/SON PCB Attachment Application Report. The most common measure of
package thermal performance is thermal impedance (RθJA ) measured (or modeled) from the chip junction to the
air surrounding the package surface (ambient). The mathematical expression for RθJA is:
RθJA = (TJ – T) / P
(8)
where
•
•
•
TJ = Chip junction temperature
T = Ambient temperature
P = Device power dissipation
Factors that can influence the measurement and calculation of RθJA include:
1.
2.
3.
4.
5.
Whether or not the device is board mounted
Trace size, composition, thickness, and geometry
Orientation of the device (horizontal or vertical)
Volume of the ambient air surrounding the device under test and airflow
Whether other surfaces are in close proximity to the device being tested
Due to the charge profile of Li-Ion and Li-Pol batteries the maximum power dissipation is typically seen at the
beginning of the charge cycle when the battery voltage is at its lowest. Typically after fast charge begins the pack
voltage increases to ≉3.4V within the first 2 minutes. The thermal time constant of the assembly typically takes a
few minutes to heat up so when doing maximum power dissipation calculations, 3.4V is a good minimum voltage
to use. This is verified, with the system and a fully discharged battery, by plotting temperature on the bottom of
the PCB under the IC (pad should have multiple vias), the charge current and the battery voltage as a function of
time. The fast charge current will start to taper off if the part goes into thermal regulation.
The device power dissipation, P, is a function of the charge rate and the voltage drop across the internal
PowerFET. It can be calculated from the following equation when a battery pack is being charged:
P = [V(IN) – V(OUT)] × I(OUT) + [V(OUT) – V(BAT)] × I(BAT)
(9)
The thermal loop feature reduces the charge current to limit excessive IC junction temperature. It is
recommended that the design not run in thermal regulation for typical operating conditions (nominal input voltage
and nominal ambient temperatures) and use the feature for non typical situations such as hot environments or
higher than normal input source voltage. With that said, the IC will still perform as described, if the thermal loop
is always active.
11.3.1 Leakage Current Effects on Battery Capacity
To determine how fast a leakage current on the battery will discharge the battery is an easy calculation. The time
from full to discharge can be calculated by dividing the Amp-Hour Capacity of the battery by the leakage current.
For a 0.75AHr battery and a 10μA leakage current (750 mAHr / 0.010 mA = 75000 hours), it would take 75k
hours or 8.8 years to discharge. In reality the self discharge of the cell would be much faster so the 10μA
leakage would be considered negligible.
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Product Folder Links: BQ24040 BQ24041 BQ24045
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SLUS941H – SEPTEMBER 2009 – REVISED FEBRUARY 2021
12 Device and Documentation Support
12.1 Device Support
12.1.1 Third-Party Products Disclaimer
TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT
CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES
OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER
ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.
12.2 Documentation Support
12.2.1 Related Documentation
For related documentation see the following:
• BQ24040 Pin FMA Application Report
• BQ2404x FIT Rate Application Report
• BQ24040 Application Report
• QFN/SON PCB Attachment Application Report
12.3 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. Click on
Subscribe to updates to register and receive a weekly digest of any product information that has changed. For
change details, review the revision history included in any revised document.
12.4 Support Resources
TI E2E™ support forums are an engineer's go-to source for fast, verified answers and design help — straight
from the experts. Search existing answers or ask your own question to get the quick design help you need.
Linked content is provided "AS IS" by the respective contributors. They do not constitute TI specifications and do
not necessarily reflect TI's views; see TI's Terms of Use.
12.5 Trademarks
TI E2E™ is a trademark of Texas Instruments.
All trademarks are the property of their respective owners.
12.6 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled
with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may
be more susceptible to damage because very small parametric changes could cause the device not to meet its published
specifications.
12.7 Glossary
TI Glossary
This glossary lists and explains terms, acronyms, and definitions.
13 Mechanical, Packaging, and Orderable Information
The following pages include mechanical packaging and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
32
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Product Folder Links: BQ24040 BQ24041 BQ24045
PACKAGE OPTION ADDENDUM
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16-Jul-2022
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
Samples
(4/5)
(6)
BQ24040DSQR
ACTIVE
WSON
DSQ
10
3000
RoHS & Green NIPDAU | NIPDAUAG
Level-2-260C-1 YEAR
0 to 125
NXE
Samples
BQ24040DSQT
ACTIVE
WSON
DSQ
10
250
RoHS & Green NIPDAU | NIPDAUAG
Level-2-260C-1 YEAR
0 to 125
NXE
Samples
BQ24041DSQR
ACTIVE
WSON
DSQ
10
3000
RoHS & Green
NIPDAUAG
Level-2-260C-1 YEAR
0 to 125
NXF
Samples
BQ24041DSQT
ACTIVE
WSON
DSQ
10
250
RoHS & Green
NIPDAUAG
Level-2-260C-1 YEAR
0 to 125
NXF
Samples
BQ24045DSQR
ACTIVE
WSON
DSQ
10
3000
RoHS & Green NIPDAU | NIPDAUAG
Level-2-260C-1 YEAR
0 to 125
SII
Samples
BQ24045DSQT
ACTIVE
WSON
DSQ
10
250
RoHS & Green NIPDAU | NIPDAUAG
Level-2-260C-1 YEAR
0 to 125
SII
Samples
(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.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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