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bq51050B, bq51051B, bq51052B
SLUSB42F – JULY 2012 – REVISED JUNE 2017
bq5105xB High-Efficiency Qi v1.2-Compliant Wireless Power Receiver
and Battery Charger
1 Features
3 Description
•
The bq5105x device is a high-efficiency, Qi-compliant
wireless power receiver with an integrated Li-Ion/LiPol battery charge controller for portable applications.
The bq5105xB devices provide efficient AC-DC
power conversion, integrates the digital controller
required to comply with Qi v1.2 communication
protocol, and provides all necessary control
algorithms needed for efficient and safe Li-Ion and LiPol battery charging. Together with the bq500212A
transmitter-side controller, the bq5105x enables a
complete wireless power transfer system for direct
battery charger solutions. By using near-field
inductive power transfer, the receiver coil embedded
in the portable device can pick up the power
transmitted by transmitter coil. The AC signal from
the receiver coil is then rectified and conditioned to
apply power directly to the battery. Global feedback
is established from the receiver to the transmitter to
stabilize the power transfer process. This feedback is
established by using the Qi v1.2 communication
protocol.
1
•
•
•
•
Single-Stage Wireless Power Receiver
and Li-Ion/Li-Pol Battery Charger
– Combines Wireless Power Receiver, Rectifier,
and Battery Charger in a Single, Small
Package
– 4.20-V, 4.35-V, and 4.40-V Output Voltage
Options
– Supports a Charging Current up to 1.5 A
– 93% Peak AC-DC Charging Efficiency
Robust Architecture
– 20-V Maximum Input Voltage Tolerance,
With Input Overvoltage Protection
– Thermal Shutdown and Overcurrent Protection
– Temperature Monitoring and Fault Detection
Compatible With WPC v1.2 Qi Industry Standard
Power Stage Output Tracks Rectifier and Battery
Voltage to Ensure Maximum Efficiency Across the
Full Charge Cycle
Available in Small DSGBA and VQFN Packages
The bq5105xB devices integrate a low-impedance
synchronous rectifier, low-dropout regulator (LDO),
digital control, charger controller, and accurate
voltage and current loops in a single package. The
entire power stage (rectifier and LDO) use lowresistance N-MOSFETs (100-mΩ typical Rdson) to
ensure high efficiency and low power dissipation.
2 Applications
•
•
•
•
•
Battery Packs
Cell Phones and Smart Phones
Headsets
Portable Media Players
Other Handheld Devices
Device Information(1)
PART NUMBER
bq51050B
bq51051B
bq51052B
PACKAGE
BODY SIZE (NOM)
VQFN (20)
4.50 mm × 3.50 mm
DSBGA (28)
3.00 mm × 1.90 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Typical Application Schematic
bq5105xB
AD-EN
AD
BAT
CCOMM1
C4
COMM1
CBOOT1
D1
BOOT1
RECT
C1
AC1
TI
Wireless
Power
Transmitter
R4
C3
TX
COIL
RX
COIL
C2
PACK+
NTC
TS/CTRL
AC2
BOOT2
CBOOT2
ROS
COMM2
CCLAMP2
CCLAMP1
CLAMP2
TERM
CLAMP1
EN2
ILIM
R1
PACK-
CHG
CCOMM2
FOD
PGND
Tri-State
Bi-State
R5
HOST
RFOD
Copyright © 2016, Texas Instruments Incorporated
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
bq51050B, bq51051B, bq51052B
SLUSB42F – JULY 2012 – REVISED JUNE 2017
www.ti.com
Table of Contents
1
2
3
4
5
6
7
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Device Options.......................................................
Pin Configuration and Functions .........................
Specifications.........................................................
7.1
7.2
7.3
7.4
7.5
7.6
8
1
1
1
2
4
4
6
Absolute Maximum Ratings ...................................... 6
ESD Ratings.............................................................. 6
Recommended Operating Conditions....................... 6
Thermal Information .................................................. 6
Electrical Characteristics........................................... 7
Typical Characteristics ............................................ 10
Detailed Description ............................................ 13
8.1 Overview ................................................................. 13
8.2 Functional Block Diagram ....................................... 14
8.3 Feature Description................................................. 14
8.4 Device Functional Modes........................................ 27
9
Application and Implementation ........................ 28
9.1 Application Information............................................ 28
9.2 Typical Application .................................................. 28
10 Power Supply Recommendations ..................... 33
11 Layout................................................................... 33
11.1 Layout Guidelines ................................................. 33
11.2 Layout Example .................................................... 33
12 Device and Documentation Support ................. 34
12.1
12.2
12.3
12.4
12.5
12.6
12.7
Documentation Support ........................................
Related Links ........................................................
Receiving Notification of Documentation Updates
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
34
34
34
34
34
34
34
13 Mechanical, Packaging, and Orderable
Information ........................................................... 34
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision E (March 2015) to Revision F
Page
•
Changed all Qi v1.1 and WPC v1.1 To: Qi v1.2 and WPC v1.2 throughout the document ................................................... 1
•
Added the Adaptive Communication Limit section ............................................................................................................... 24
•
Deleted R1 = 29.402 kΩ R3 = 14.302 kΩ and added a link to SLUS629 in the Internal Temperature Sense (TS
Function of the TS/CTRL Pin) section ................................................................................................................................. 25
Changes from Revision D (January 2014) to Revision E
Page
•
Added ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation
section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and
Mechanical, Packaging, and Orderable Information section .................................................................................................. 1
•
Added the bq51052B 4.40-V option ....................................................................................................................................... 1
•
Updated pinout images........................................................................................................................................................... 4
•
Added thermal pad description in Pin Functions table ........................................................................................................... 4
•
Added AD voltage to Recommended Operating Conditions .................................................................................................. 6
•
Changed RECT overvoltage specification name from VRECT to VOVP ..................................................................................... 7
•
Changed to ILIM_SHORT, OK from ILIM_SC for clarity...................................................................................................................... 7
•
Added VOREG for bq51052B .................................................................................................................................................... 8
•
Added minimum current for KILIM ............................................................................................................................................ 8
•
Changed KILIM TYP value from 300 to 314 (min / max also changed) ................................................................................... 8
•
Added IBULK spec for charging minimum and maximum......................................................................................................... 8
•
Added VRECH for bq51052B .................................................................................................................................................... 8
•
Added new spec ITermination ...................................................................................................................................................... 8
•
Changed to VTSB from VTS for clarity................................................................................................................................... 8
•
Changed from ITS-Bias for clarity ............................................................................................................................................... 8
•
Deleted V0C-F as redundant..................................................................................................................................................... 8
•
Changed typical JEITA regulation on bq51050B from 4.10 V to 4.06 V ................................................................................ 8
2
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Copyright © 2012–2017, Texas Instruments Incorporated
Product Folder Links: bq51050B bq51051B bq51052B
bq51050B, bq51051B, bq51052B
www.ti.com
SLUSB42F – JULY 2012 – REVISED JUNE 2017
•
Changed to clarify CTRL pin high and low levels................................................................................................................... 8
•
Changed Thermal shutdown name to TJ-SD for clarity ............................................................................................................ 9
•
Added section to describe Adapter Enable function............................................................................................................... 9
•
Changed Synchronous rectifer switchover name to IBAT-SR for clarity..................................................................................... 9
•
Added synchronous mode entry for bq51052B ...................................................................................................................... 9
•
Deleted note regarding internal junction monitor reducing current - it is not applicable. ..................................................... 19
•
Added section on modified JEITA profile for bq51052B....................................................................................................... 21
•
Changed TS/CTRL function to correct Termination Packet value........................................................................................ 22
•
Added Taper mode completion for Termination Packet ....................................................................................................... 22
•
Changed Beta value from 4500 to 3380 to match NTC datasheet ...................................................................................... 25
•
Changed received power maximum error from 250 mW to 375 mW to comply with latest WPC v1.2 specification ........... 27
Changes from Revision C (February 2013) to Revision D
Page
•
Changed the ABSOLUTE MAXIMUM RATINGS - moved AC1 and AC2 onto a single row with a Min value of –0.8 ......... 6
•
Added section: Details of a Qi Wireless Power System and bq5105xB Power Transfer Flow Diagrams............................ 15
•
Changed text in the Battery Charge Profile section ............................................................................................................. 19
•
Changed Battery failure Conditions in Table 1..................................................................................................................... 22
•
Changed Equation 3 and Equation 4 ................................................................................................................................... 25
•
Changed R2 = 7.81 kΩ To: R1 = 29.402 kΩ ......................................................................................................................... 25
•
Changed R3 = 13.98 kΩ To: R3 = 14.302 kΩ in the Internal Temperature Sense (TS Function of the TS/CTRL Pin)
section .................................................................................................................................................................................. 25
•
Changed THOT = 0°C To: THOT = 60°C.................................................................................................................................. 25
•
Changed Equation 6............................................................................................................................................................. 29
Changes from Revision B (September 2012) to Revision C
•
Page
First release of the full data sheet .......................................................................................................................................... 1
Changes from Revision A (August 2012) to Revision B
Page
•
Changed last features bullet from: 1.9 x 3.0mm WCSP and 4.5 x 3.5mm QFN Package Options to: Available in
small WCSP and QFN packages ........................................................................................................................................... 1
•
Changed Figure 1 and changed caption from: Wireless Power Consortium (WPC or Qi) Inductive Power Charging
System, to: Typical System blocks shows bq5105xB used as a Wireless Power Li-Ion/Li-Pol Battery Charger................... 1
•
Added note: Visit ti.com/wirelesspower for product details and design resources................................................................. 1
Changes from Original (August 2012) to Revision A
Page
•
Changed Regulated BAT(output) voltage............................................................................................................................... 8
•
Changed Recharge threshold for bq51052B .......................................................................................................................... 8
•
Deleted ITS-Bias-Max .................................................................................................................................................................... 8
•
Changed VCOLD to VOC and values ......................................................................................................................................... 8
•
Changed V45C values .............................................................................................................................................................. 8
•
Changed V60C values .............................................................................................................................................................. 8
•
Changed Figure 25............................................................................................................................................................... 21
•
Changed Figure 25............................................................................................................................................................... 22
Copyright © 2012–2017, Texas Instruments Incorporated
Product Folder Links: bq51050B bq51051B bq51052B
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bq51050B, bq51051B, bq51052B
SLUSB42F – JULY 2012 – REVISED JUNE 2017
www.ti.com
5 Device Options
DEVICE
FUNCTION
VRECT-OVP
VRECT-REG
VBAT-REG
NTC MONITORING
bq51050B
4.20-V Li-Ion Wireless Battery Charger
15 V
Track
4.20 V
JEITA
bq51051B
4.35-V Li-Ion Wireless Battery Charger
15 V
Track
4.35 V
JEITA
bq51052B
4.40-V Li-Ion Wireless Battery Charger
15 V
Track
4.40 V
Modified JEITA
6 Pin Configuration and Functions
YFP Package
28-Pin DSBGA
Top View
4
A
PGND
PGND
PGND
PGND
B
AC2
AC2
AC1
AC1
BAT
BAT
BAT
COMM2
CLAMP2
CLAMP1
COMM1
F
TS/CTRL
FOD
AD-EN
CHG
G
ILIM
EN2
TERM
AD
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BOOT1
3
18
RECT
BAT
4
17
BOOT2
CLAMP1
5
16
CLAMP2
Thermal
BOOT1
E
4
AC2
Pad
COMM1
6
15
COMM2
CHG
7
14
FOD
AD-EN
8
13
TS/CTRL
AD
9
12
ILIM
11
RECT
19
EN2
BAT
RECT
2
10
D
BOOT2
AC1
TERM
C
PGND
3
20
2
PGND
1
1
RHL Package
20-Pin VQFN With Exposed Thermal Pad
Top View
The exposed thermal pad should be
connected to ground.
Copyright © 2012–2017, Texas Instruments Incorporated
Product Folder Links: bq51050B bq51051B bq51052B
bq51050B, bq51051B, bq51052B
www.ti.com
SLUSB42F – JULY 2012 – REVISED JUNE 2017
Pin Functions
Pin
VQFN
I/O
DESCRIPTION
NAME
DSBGA
AC1
B3, B4
2
I
Input power from receiver coil.
AC2
B1, B2
19
I
Input power from receiver coil.
AD
G4
9
I
If AD functionality is used, connect this pin to the wired adapter input. When VAD-Pres is applied to
this pin wireless charging is disabled and AD_ENn is driven low. Connect a 1-µF capacitor from AD
to PGND. If unused, the capacitor is not required and AD should be connected directly to PGND.
AD-EN
F3
8
O
Push-pull driver for external PFET when wired charging is active. Float if not used.
4
O
Output pin, delivers power to the battery while applying the internal charger profile.
D1
BAT
D2
D3
D4
BOOT1
C4
3
O
BOOT2
C1
17
O
Bootstrap capacitors for driving the high-side FETs of the synchronous rectifier. Connect a 10-nF
ceramic capacitor from BOOT1 to AC1 and from BOOT2 to AC2.
CHG
F4
7
O
Open-drain output – active when BAT is enabled. Float if not used.
CLAMP1
E3
5
O
CLAMP2
E2
16
O
Open-drain FETs which are used for a non-power dissipative overvoltage AC clamp protection.
When the RECT voltage goes above 15 V, both switches will be turned on and the capacitors will
act as a low impedance to protect the device from damage. If used, capacitors are used to connect
CLAMP1 to AC1 and CLAMP2 to AC2. Recommended connections are 0.47-µF capacitors.
COMM1
E4
6
O
COMM2
E1
15
O
EN2
G2
11
I
Used to set priority between wireless power and wired power. EN2 low enables wired charging
source if AD input voltage is present. EN2 high disables wired charging source and wireless power
is enabled if present.
FOD
F2
14
I
Input for the rectified power measurement. See WPC v1.2 Compatibility for details.
ILIM
G1
12
I/O
1, 20
–
Power ground
Open-drain outputs used to communicate with primary by varying reflected impedance. Connect a
capacitor from COMM1 to AC1 and a capacitor from COMM2 to AC2 for capacitive load modulation.
For resistive modulation connect COMM1 and COMM2 to RECT through a single resistor. See
Communication Modulator for more information.
Programming pin for the battery charge current. The total resistance from ILIM to PGND (RILIM) sets
the charge current. Figure 32 shows RILIM to be R1 + RFOD. Details can be found in Electrical
Characteristics and Battery Charge Current Setting Calculations.
A1
PGND
A2
A3
A4
RECT
C2, C3
18
O
Filter capacitor for the internal synchronous rectifier. Connect a ceramic capacitor to PGND.
Depending on the power levels, the value may be from 4.7 μF to 22 μF.
TERM
G3
10
I
Input that is used to set the termination threshold. Termination current is the battery current level
below which the charge process will cease. The termination current is set as a percentage of the
charge current. See Battery Charge Current Setting Calculations for more details.
Temperature Sense (TS) and Control (CTRL) pin functionality. For the TS functionality connect
TS/CTRL to ground through a Negative Temperature Coefficient (NTC) resistor. If an NTC function
is not desired, connect to PGND with a 10-kΩ resistor. As a CTRL pin pull low to send end power
transfer (EPT) fault to the transmitter or pull up to an internal rail to send EPT termination to the
transmitter. See Internal Temperature Sense (TS Function of the TS/CTRL Pin) for more details.
TS/CTRL
F1
13
I
—
—
PAD
—
The exposed thermal pad should be connected to ground (PGND).
Copyright © 2012–2017, Texas Instruments Incorporated
Product Folder Links: bq51050B bq51051B bq51052B
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bq51050B, bq51051B, bq51052B
SLUSB42F – JULY 2012 – REVISED JUNE 2017
www.ti.com
7 Specifications
7.1 Absolute Maximum Ratings (1) (2)
over operating free-air temperature range (unless otherwise noted)
Input voltage
MIN
MAX
UNIT
RECT, COMM1, COMM2, BAT, CHG, CLAMP1, CLAMP2
–0.3
20
V
AC1, AC2
–0.8
20
V
AD, AD-EN
–0.3
30
V
BOOT1, BOOT2
–0.3
26
V
EN2, TERM, FOD, TS/CTRL, ILIM
–0.3
7
V
2
A(RMS)
1.5
A
CHG
15
mA
COMM1, COMM2
1.0
A
Input current
AC1, AC2
Output current
BAT
Output sink current
Junction temperature, TJ
–40
150
°C
Storage temperature, Tstg
–65
150
°C
(1)
(2)
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 voltages are with respect to the VSS terminal, unless otherwise noted.
7.2 ESD Ratings
VALUE
V(ESD)
(1)
(2)
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001
Electrostatic discharge
(1)
UNIT
±2000
Charged-device model (CDM), per JEDEC specification JESD22-C101 (2)
V
±500
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.
7.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
VIN
Input voltage range
RECT
IIN
Input current
Internal Rectifier (voltage monitored at RECT node)
MIN
MAX
UNIT
4
10
V
1.5
A
bq51050B, bq51051B
1.5
bq51052B
0.8
IBAT
BAT(output) current
BAT
VAD
Adapter voltage
AD
15
V
IAD-EN
Sink current
AD-EN
1
mA
ICOMM
COMM sink current
COMM
500
mA
TJ
Junction temperature
125
°C
0
A
7.4 Thermal Information
bq51050B, bq51051B, bq51052B
THERMAL METRIC
(1)
YFP (DSGBA)
RHL (VQFN)
28 PINS
20 PINS
UNIT
RθJA
Junction-to-ambient thermal resistance
58.9
37.7
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
0.2
35.5
°C/W
RθJB
Junction-to-board thermal resistance
9.1
13.6
°C/W
ψJT
Junction-to-top characterization parameter
1.4
0.5
°C/W
ψJB
Junction-to-board characterization parameter
8.9
13.5
°C/W
(1)
6
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
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Copyright © 2012–2017, Texas Instruments Incorporated
Product Folder Links: bq51050B bq51051B bq51052B
bq51050B, bq51051B, bq51052B
www.ti.com
SLUSB42F – JULY 2012 – REVISED JUNE 2017
Thermal Information (continued)
bq51050B, bq51051B, bq51052B
THERMAL METRIC (1)
RθJC(bot)
YFP (DSGBA)
RHL (VQFN)
28 PINS
20 PINS
n/a
2.7
Junction-to-case (bottom) thermal resistance
UNIT
°C/W
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
2.6
2.7
2.8
UNIT
VUVLO
Undervoltage lockout
VRECT: 0 V → 3 V
VHYS-UVLO
Hysteresis on UVLO
VRECT: 3 V → 2 V
VOVP
Input overvoltage threshold
VRECT: 5 V → 16 V
VHYS-OVP
Hysteresis on OVP
VRECT: 16 V → 5 V
VRECT-REG (1)
VRECT regulation voltage
ILOAD
ILOAD Hysteresis for dynamic VRECT thresholds as a %
of IILIM
ILOAD falling
5%
VTRACK
Tracking VRECT regulation above VBAT
VBAT = 3.5 V,
IBAT ≥ 500 mA
300
VRECT-REV
Rectifier reverse voltage protection at the BAT(output)
VRECT-REV = VBAT – VRECT,
VBAT = 10 V
8.3
9
V
VRECT-DPM
Rectifier undervoltage protection, restricts IBAT at
VRECT-DPM
3.1
3.2
V
IBAT = 0 mA, 0°C ≤ TJ ≤ 85°C
8
10
mA
IBAT = 300 mA, 0°C ≤ TJ ≤ 85°C
2
3
mA
12
20
µA
250
14.5
3
15
V
mV
15.5
V
150
mV
5.11
V
mV
QUIESCENT CURRENT
IRECT
Active chip quiescent current consumption from RECT
(when wireless power is present)
IQ
Quiescent current at the BAT when wireless power is
disabled (Standby)
VBAT = 4.2 V, 0°C ≤ TJ ≤ 85°C
ILIM SHORT PROTECTION
RILIM-SHORT
tDGL-Short
ILIM_SHORT,
OK
Highest value of ILIM resistor considered a fault
(short).
Monitored for IBAT > ILIM_SHORT, OK
RILIM: 200 Ω → 50 Ω. IBAT
latches off, cycle power to
reset
bq51050B,
bq51051B
120
bq51052B
235
Deglitch time transition from ILIM short to IBAT disable
1
ms
bq51050B,
bq51051B
110
145
165
bq51052B
55
75
95
ILIM-SHORT,OK enables the IILIM short comparator when
IBAT is greater than this value
IBAT: 0 mA → 200 mA
Hysteresis for ILIM-SHORT,OK comparator
IBAT: 200 mA → 0 mA
Maximum output current limit
Maximum IBAT that will be delivered for up
to 1 ms when ILIM is shorted to PGND
Ω
mA
ILIM-SHORT,
OK
30
mA
HYSTERESIS
IBAT-CL
2.4
A
BATTERY SHORT PROTECTION
VBAT(SC)
BAT pin short-circuit detection/precharge threshold
VBAT: 3 V → 0.5 V, no deglitch
VBAT(SC)-HYS
VBAT(SC) hysteresis
VBAT: 0.5 V → 3 V
IBAT(SC)
Source current to BAT pin during short-circuit
detection
VBAT = 0 V
0.75
0.8
0.85
100
V
mV
bq51050B,
bq51051B
12
18
22
bq51052B
12
18
25
mA
VOLTAGE REGULATION PHASE
IEndTrack
(1)
IBAT threshold during Voltge Regulation Phase that
changes VRECT level from VBAT+VTRACK to VRECT-REG
IBAT decreasing
bq51050B,
bq51051B
0.35 *
IBULK
bq51052B
0.05 *
IBULK
mA
VRECT-REG is overridden when rectifier foldback mode is active (VRECT-REG-VTRACK).
Copyright © 2012–2017, Texas Instruments Incorporated
Product Folder Links: bq51050B bq51051B bq51052B
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SLUSB42F – JULY 2012 – REVISED JUNE 2017
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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
2.9
3.0
3.1
18%
20%
23%
UNIT
PRECHARGE
VBAT: 2 V → 4 V
VLOWV
Precharge to fast charge transition threshold
KPRECHG
Precharge current as a percentage of the programmed VLOWV > VBAT > VBAT(SC)
charge current setting (IBULK)
IBAT: 50 mA – 300 mA
IPRECHG
IBAT during precharge
VLOWV > VBAT > VBAT(SC), IBULK = 500 mA
tprecharge
Precharge time-out
VBAT(SC) < VBAT < VLOWV
tDGL1(LOWV)
tDGL2(LOWV)
V
100
mA
30
min
Deglitch time, pre- to fast-charge
25
ms
Deglitch time, fast- to precharge
25
ms
OUTPUT
VOREG
Regulated BAT(output) voltage
VDO
IBAT = 1000 mA
Drop-out voltage, RECT to BAT
KILIM
4.16
4.20
4.22
bq51051B
4.30
4.35
4.37
bq51052B
4.36
4.40
4.44
110
190
mV
314
321
AΩ
IBAT = 1 A
Current programming factor
IBULK
bq51050B
Battery charging current limits
RLIM = KILIM / IIBULK (500
mA - 1.5 A)
bq51050B,
bq51051B
RLIM = KILIM / IIBULK (500
mA - 1.0 A)
bq51052B
KILIM 303 to 321
tfast-charge
Fast-charge timer
IBAT-R
Battery charge current limit programming range
ICOMM-CL
Current limit during communication
303
bq51050B,
bq51051B
500
1,500
bq51052B
500
1,000
VLOWV < VBAT < VBAT-REG
10
V
mA
hours
1500
mA
330
390
420
mA
200
240
280
Ω/%
TERMINATION
KTERM
Programmable termination current as a percentage of
IIBULK
RTERM = %IIBULK x KTERM (IBULK = 500 mA)
ITERM-Th
Termination current from BAT, defined with KTERM, as
the current that terminates the charge cycle
IBAT decreasing, RTERM = 2.4k Ω, IBULK =
1000 mA
ITERM
Constant current at the TERM pin to bias the
termination reference
VRECH
Recharge threshold
ITermination
100
mA
40
50
55
bq51050B
VBAT-REG
–135mV
VBAT-REG
–110mV
VBAT-REG
–90mV
bq51051B
VBAT-REG
–125mV
VBAT-REG
–95mV
VBAT-REG
–70mV
bq51052B
VBAT-REG
–125mV
VBAT-REG
–95mV
VBAT-REG
–70mV
Termination current setting limits
120
µA
V
mA
TS / CTRL FUNCTIONALITY
VTSB
Internal TS bias voltage (VTS is the voltage at the
TS/CTRL pin, VTSB is the internal bias voltage)
ITSB< 100 µA (periodically
driven see tTS/CTRL-Meas)
V0C-R
Rising threshold
VTS: 50% → 60%
V0C-Hyst
Hysteresis on 0°C Comparator
VTS: 60% → 50%
V10C
Rising threshold
VTS: 40% → 50%
V10C-Hyst
Hysteresis on 10°C Comparator
VTS: 50% → 40%
V45C
Falling threshold
VTS: 25% → 15%
V45C-Hyst
Hysteresis on 45°C Comparator
VTS: 15% → 25%
V60C
Falling threshold
VTS: 20% → 5%
V60C-Hyst
Hysteresis on 60°C Comparator
VTS: 5% → 20%
I45C
IBULK reduction percentage at 45°C (in full JEITA mode
VTS: 25% → 15%, IBAT = IBULK
- N/A for bq51052B)
VO-J
Voltage regulation during JEITA temperature range
VCTRL-HI
8
2.2
2.4
V
57
58.7
60
%VTSB
2.4
46
47.8
%VTSB
49
2
18
19.6
12
13.1
50%
bq51050B
4.06
bq51051B
4.2
bq51052B
4.2
0.2
%VTSB
%VTSB
14
1
45%
%VTSB
%VTSB
21
3
Voltage on CTRL pin for a high
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2
%VTSB
%VTSB
55%
V
5
V
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SLUSB42F – JULY 2012 – REVISED JUNE 2017
Electrical Characteristics (continued)
Over junction temperature range 0°C ≤ TJ ≤ 125°C and recommended supply voltage (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
0
MAX
Voltage on CTRL pin for a low
tTS/CTRL-Meas
Time period of TS/CTRL measurements (when VTSB is TS bias voltage is only driven when
being driven internally)
communication packets are sent
24
ms
tTS-Deglitch
Deglitch time for all TS comparators
10
ms
NTC-Pullup
Pullup resistor for the NTC network. Pulled up to the
TS bias LDO.
NTC-RNOM
Nominal resistance requirement at 25°C of the NTC
resistor
10
kΩ
NTC-Beta
Beta requirement for accurate temperature sensing
through the above specified thresholds
3380
Ω
155
°C
20
°C
18
0.1
UNIT
VCTRL-LOW
20
22
V
kΩ
THERMAL PROTECTION
TJ-SD
Thermal shutdown temperature
TJ-Hys
Thermal shutdown hysteresis
OUTPUT LOGIC LEVELS ON CHG
VOL
IOFF,CHG
Open-drain CHG pin
ISINK = 5 mA
CHG leakage current when disabled
VCHG = 20 V,
0°C ≤ TJ ≤ 85°C
COMM1 and COMM2
VRECT = 2.6 V
500
mV
1
µA
COMM PIN
RDSON(COMM)
fCOMM
IOFF,COMM
Signaling frequency on COMM pin
1
Ω
2
kb/s
VCOMM1 = 20 V,
VCOMM2 = 20 V
COMM pin leakage current
1
µA
CLAMP PIN
RDS-
CLAMP1 and CLAMP2
0.75
Ω
ON(CLAMP)
ADAPTER ENABLE
VAD-Pres
VAD Rising threshold voltage. EN-UVLO
VAD 0 V → 5 V
VAD-PresH
VAD-Pres hysteresis, EN-HYS
VAD 5 V → 0 V
IAD
Input leakage current
VRECT = 0 V, VAD = 5 V
RAD
Pullup resistance from AD-EN to BAT when adapter
mode is disabled and VBAT > VAD, EN-OUT
VAD = 0 V, VBAT = 5 V
VAD-Diff
Voltage difference between VAD and VAD-EN when
adapter mode is enabled, EN-ON
VAD = 5 V, 0°C ≤ TJ ≤ 85°C
3.5
3.6
3.8
400
V
mV
60
µA
200
350
Ω
3
4.5
5
V
bq51050B,
bq51051B
80
115
140
bq51052B
20
50
65
SYNCHRONOUS RECTIFIER
IBAT-SR
IBAT at which the synchronous rectifier enters half
synchronous mode, SYNC_EN
IBAT-SRH
Hysteresis for IBAT,SR (full-synchronous mode enabled)
VHS-DIODE
High-side diode drop when the rectifier is in half
synchronous mode
IBAT 200 mA → 0 mA
IBAT 0 mA → 200 mA
bq51050B,
bq51051B
25
bq51052B
28
IAC-VRECT = 250 mA, and TJ = 25°C
0.7
mA
V
EN2
VIL
Input low threshold for EN2
VIH
Input high threshold for EN2
RPD, EN
EN2 pulldown resistance
0.4
1.3
V
V
200
kΩ
0.25
W
ADC
PowerREC
0 W – 5 W received power after calibration
of Rx magnetics losses
Received power measurement
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7.6 Typical Characteristics
100
100
90
90
80
Efficiency (%)
Efficiency (%)
70
80
70
60
60
50
40
30
20
50
Pre-charge & fast charge mode
Taper mode
10
40
0
0
0.00
5
4
2
3
Output Power (W)
Figure 1. Rectifier Efficiency
1
2.00
3.00
4.00
5.00
Output Power (W)
Figure 2. IC Efficiency (AC Input to DC Output)
5.50
1.00
6.0
5.00
Rectifier Voltage (V)
Vrect and Vbat (V)
5.0
Vrect
4.50
4.00
3.50
3.00
Vbat
4.0
3.0
2.50
Pre-charge & fast charge mode
Taper mode
2.0
Precharge & fast charge mode
Taper mode
2.00
1.50
0.00
RILIM=600W
0.20
0.40
0.60
0.80
1.00
Output Current (A)
Figure 3. VRECT, VBAT versus Output Current
1.0
0.0
0.1
0.2
0.3
0.4
0.5
0.6
Output Current (A)
Figure 4. VRECT versus Output Current at RILIM=600 Ω (ILIM =
523 mA)
0.008
70
Pre-charge & fast charge mode
Taper mode
0.007
60
0.005
Efficiency (%)
Output Ripple (V)
0.006
0.004
0.003
50
40
30
0.002
20
0.001
0
10
0
0.2
0.4
0.6
0.8
1
1.2
Output Current (A)
Figure 5. Output Ripple versus Output Current
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4
2
3
Output Power (W)
Figure 6. System Efficiency (DC Input to DC Output)
0
1
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SLUSB42F – JULY 2012 – REVISED JUNE 2017
100%
100%
90%
90%
80%
80%
70%
70%
60%
60%
Efficiency
Efficiency
Typical Characteristics (continued)
50%
40%
40%
30%
30%
20%
20%
10%
10%
0
0
3
3.3
3.6
3.9
4.2
VBAT (V)
4.5
0
0.06
D001
Figure 7. bq51052B 300-mA Fast Charge Efficiency (DC
Input to DC Output)
100%
100%
90%
90%
80%
80%
70%
70%
60%
60%
50%
40%
0.24
0.3
D001
50%
40%
30%
30%
20%
20%
10%
10%
0
0.12
0.18
IBAT during Taper Mode (A)
Figure 8. bq51052B 300-mA Taper Charge Efficiency (DC
Input to DC Output)
Efficiency
Efficiency
50%
0
3
3.3
3.6
3.9
VBAT (V)
4.2
4.5
D001
Figure 9. bq51052B 800-mA Fast Charge Efficiency (DC
Input to DC Output)
0
0.2
0.4
0.6
IBAT during Taper Mode (A)
0.8
1
D001
Figure 10. bq51052B 800-mA Taper Charge Efficiency (DC
Input to DC Output)
VRECT
VRECT
VBAT
VBAT
IBAT
IBAT
Figure 11. Battery Insertion in Precharge Mode
Figure 12. Battery Insertion in Fast-Charge Mode
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Typical Characteristics (continued)
VRECT
VRECT
VTS/CTRL
VTS/CTRL
VBAT
VBAT
IBAT
IBAT
Figure 13. TS Fault
Figure 14. TS Ground Fault
VTS/CTRL
VRECT
VRECT
VBAT
IBAT
VBAT
IBAT
Figure 15. Precharge to Fast-Charge Transition
Figure 16. JEITA Functionality (Rising Temp) bq51050B/bq51051B
VRECT
VRECT
VTS/CTRL
VBAT
IBAT
Figure 17. JEITA Functionality (Falling Temp) bq51050B/bq51051B
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IBAT
VBAT
Figure 18. Battery Short to Precharge Mode Transition
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SLUSB42F – JULY 2012 – REVISED JUNE 2017
8 Detailed Description
8.1 Overview
8.1.1 A Brief Description of the Wireless System
A wireless system consists of a charging pad (primary, transmitter) and the secondary-side equipment. There are
coils in the charging pad and in the secondary equipment which magnetically couple to each other when the
equipment is placed on the charging pad. Power is transferred from the primary to the secondary by transformer
action between the coils. Control over the amount of power transferred is achieved by changing the frequency of
the primary drive.
The secondary can communicate with the primary by changing the load seen by the primary. This load variation
results in a change in the primary coil current, which is measured and interpreted by a processor in the charging
pad. The communication is digital - packets are transferred from the secondary to the primary. Differential biphase encoding is used for the packets. The rate is 2-kbps.
Various types of communication packets have been defined. These include identification and authentication
packets, error packets, control packets, power usage packets, end of power packet and efficiency packets.
The primary coil is powered off most of the time. It wakes up occasionally to see if a secondary is present. If a
secondary authenticates itself to the primary, the primary remains powered up. The secondary maintains full
control over the power transfer using communication packets.
Power
AC to DC
Drivers
bq5105x
Rectification
Voltage/
Current
Conditioning
System
Communication
Controller
V/I
Sense
Controller
Battery
Charger
LI-Ion
Battery
bq500210
Transmitter
Receiver
Figure 19. WPC Wireless Power Charging System Indicating the Functional Integration of the bq5105x
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8.2 Functional Block Diagram
,
BAT
VREF,ILIM
VILIM
VOUT,FB
+
_
+
_
RECT
VOUT,REG
VREF,IABS
VIABS,FB
+
_
VIN,FB
VIN,DPM
+
_
ILIM
AD
+
_
VREFAD,OVP
BOOT2
+
_
BOOT1
VREFAD,UVLO
AD-EN
AC1
AC2
Sync
Rectifier
Control
VREF,TS-BIAS
VFOD
+
_
COMM1
TS_0
COMM2
DATA_
OUT
ADC
CLAMP1
CLAMP2
VBG,REF
VIN,FB
VOUT,FB
VILIM
VIABS,FB
TS_10
TS_45
VIABS,REF
VIC,TEMP
Digital Control
and Charger
TS_60
VFOD
TS_DETECT
50µ A
+
_
+
_
+
_
+
_
TS/CTRL
+
_
+
_
VREF_100MV
VRECT
VOVP,REF
TERM
+
OVP
TERM
CHG
FOD
ILIM
_
EN2
200k:
PGND
Copyright © 2016, Texas Instruments Incorporated
8.3 Feature Description
8.3.1 Using the bq5105x as a Wireless Li-Ion/Li-Pol Battery Charger (With Reference to Functional Block
Diagram)
Functional Block Diagram is the schematic of a system which uses the bq5105x as a direct battery charger.
When the system shown in Functional Block Diagram is placed on the charging pad (transmitter), the receiver
coil couples to the magnetic flux generated by the coil in the charging pad which consequently induces a voltage
in the receiver coil. The internal synchronous rectifier feeds this voltage to the RECT pin which has the filter
capacitor C3.
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SLUSB42F – JULY 2012 – REVISED JUNE 2017
Feature Description (continued)
The bq5105x identifies and authenticates itself to the primary using the COMM pins by switching on and off the
COMM FETs and hence switching in and out CCOMM. If the authentication is successful, the transmitter will
remain powered on. The bq5105x measures the voltage at the RECT pin, calculates the difference between the
actual voltage and the desired voltage VRECT-REG and sends back error packets to the primary. This process goes
on until the RECT voltage settles at VRECT-REG.
During power-up, the LDO is held off until the VRECT-REG threshold converges. The voltage control loop ensures
that the output (BAT) voltage is maintained at VBAT-REG. The values of VBAT and VRECT are dependant on the
battery charge mode. The bq5105x continues to monitor the VRECT and VBAT and sends error packets to the
primary every 250 ms. The bq5105x regulates the VRECT voltage very close to battery voltage, this voltage
tracking process minimizes the voltage difference across the internal LDO and maximizes the charging efficiency.
If a large transient occurs, the feedback to the primary speeds up to every 32 ms in order to converge on an
operating point in less time.
8.3.2 Details of a Qi Wireless Power System and bq5105xB Power Transfer Flow Diagrams
The bq5105xB integrates a fully compliant WPC v1.2 communication algorithm in order to streamline receiver
designs (no extra software development required). Other unique algorithms such as Dynamic Rectifier Control
are also integrated to provide best-in-class system performance. This section provides a high level overview of
these features by illustrating the wireless power transfer flow diagram from start-up to active operation.
During start-up operation, the wireless power receiver must comply with proper handshaking to be granted a
power contract from the TX. The TX will initiate the handshake by providing an extended digital ping. If an RX is
present on the TX surface, the RX will then provide the signal strength, configuration and identification packets to
the TX (see volume 1 of the WPC specification for details on each packet). These are the first three packets sent
to the TX. The only exception is if there is a shutdown condition on the EN1/EN2, AD, or TS/CTRL pins where
the Rx will shut down the TX immediately. Once the TX has successfully received the signal strength,
configuration and identification packets, the RX will be granted a power contract and is then allowed to control
the operating point of the power transfer. With the use of the bq5105xB Dynamic Rectifier Control algorithm, the
RX will inform the TX to adjust the rectifier voltage above 5 V before enabling the output supply. This method
enhances the transient performance during system start-up. See Figure 20 for the start-up flow diagram details.
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Feature Description (continued)
TX Powered
without RX
Active
TX Extended Digital Ping
EN2/AD/TS/CTRL EPT
Condition?
YES
Send EPT packet with
reason value
NO
Identification &
Configuration & SS, Received
by TX?
NO
YES
Power Contract Established.
All proceeding control is
dictated by the RX.
VRECT < VRECT-REG ?
YES
Send control error packet to
increase VRECT
NO
Startup operating point
established. Enable the RX
output.
RX Active Power
Transfer Stage
Figure 20. Wireless Power Start-up Flow Diagram
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Feature Description (continued)
Once the start-up procedure has been established, the RX will enter the active power transfer stage. This is
considered the “main loop” of operation. The Dynamic Rectifier Control algorithm will determine the rectifier
voltage target based on a percentage of the maximum output current level setting (set by KILIM and the IILIM
resistance to PGND). The RX will send control error packets in order to converge on these targets. As the output
current changes, the rectifier voltage target will dynamically change. As a note, the feedback loop of the WPC
system is relatively slow where it can take up to 90 ms to converge on a new rectifier voltage target. It should be
understood that the instantaneous transient response of the system is open loop and dependent on the RX coil
output impedance at that operating point. More details on this will be covered in the section Receiver Coil LoadLine Analysis. The “main loop” will also determine if any conditions are true and will then discontinue the power
transfer. Figure 21 shows the active power transfer loop.
RX Active Power
Transfer Stage
RX Shutdown
conditions per
the EPT Table?
YES
Send EPT packet with
reason value
YES
VRECT target = VRECT-REG.
Send control error packets
to converge.
YES
VRECT target = VBAT + VTRACK.
Send control error packets
to converge.
TX Powered
without RX
Active
NO
VBAT < VLOWV
NO
IBAT > KPRECHG% of IBULK?
NO
VRECT target = VRECT-REG.
Send control error packets
to converge.
Measure Rectified Power
and Send Value to TX
TERM STATE
Figure 21. Active Power Transfer Flow Diagram
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Feature Description (continued)
Power
Transfer
VILIM < VTERM?
NO
VBAT > VRECH?
YES
YES
Send EPT Charge
Complete
NO
VBAT < VBAT(SC)
YES
VRECT Target = VRECT-REG
IBAT = IBAT(SC)
YES
VRECT Target = VRECT-REG
IOUT = IPRECHG
NO
VBAT(SC) < VBAT < VLOWV
NO
NO
VLOWV < VBAT < VOREG
YES
VRECT Target = VBAT + VTRACK
IBAT = IBULK
NO
IBAT < IEndTrack?
YES
VRECT Target = VRECT-REG
NO
AD / TS/CTRL
EPT Condition?
YES
Send EPT
Figure 22. TERM STATE Flow Diagram of bq5105XB
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Feature Description (continued)
8.3.3 Battery Charge Profile
The battery is charged in three phases: precharge, fast-charge constant current and constant voltage. A voltagebased battery pack thermistor monitoring input (TS function of the TS/CTRL pin) is included that monitors battery
temperature for safe charging. The TS function for bq51050B and bq51051B is JEITA compatible. The TS
function for the bq51052B modifies the current regulation differently than standard JEITA. See Battery-Charger
Safety and JEITA Guidelines for more details.
The rectifier voltage follows BAT voltage plus VTRACK for any battery voltage above VLOWV to full regulation
voltage and most of the taper charging phase. If the battery voltage is below VLOWV the rectifier voltage increases
to VRECT-REG.
If IBAT is less than IEndTrack (a percentage of IBULK) during taper mode, the rectifier voltage increases to VRECT-REG.
The charge profile for the bq51050B and bq51051B is shown in Figure 23 while the bq51052B is shown in
Figure 24.
VRECT-REG
Pre-charge
Current Regulation Phase Voltage Regulation Phase
Phase
VRECT = VBAT + VTRACK VRECT = VRECT-REG
VRECT = VRECT-REG
VOREG
VBAT = VOREG
IBAT = IBULK
IBulk
VRECT =
VBAT + VTRACK
VBAT
VLOWV
VBAT(SC)
VBAT
IEndTrack
IBAT = Taper
IBAT
IBAT = Off
VRECT-REG
Exits
VRECT-TRACK
ITERM-Th
IPRECHG
IBAT(SC)
TX Off
VRECT-TRACK
Figure 23. bq51050B and bq51051B Li-Ion Battery Charge Profile
VRECT-REG
Pre-charge
Current Regulation Phase
Phase
VRECT = VRECT-REG
Voltage Regulation Phase
VRECT = VBAT + VTRACK
VOREG
VBAT = VOREG
IBAT = IBULK
IBulk
VRECT =
VBAT + VTRACK
VBAT
VLOWV
VBAT(SC)
VBAT
IBAT = Taper
IBAT
IBAT = Off
VRECT-REG
VRECT-TRACK
ITERM-Th
IPRECHG
IBAT(SC)
TX Off
Figure 24. bq51052B Li-Ion Battery Charge Profile
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Feature Description (continued)
8.3.4 Battery Charging Process
8.3.4.1 Precharge Mode (VBAT ≤ VLOWV)
The bq5105X enters precharge mode when VBAT ≤ VLOWV. Upon entering precharge mode, battery charge
current limit is set to IPRECHG. During precharge mode, the charge current is regulated to KPRECHG percent of the
fast charge current (IBULK) setting. For example, if IBULK is set to 800 mA, then the precharge current would
have a typical value of 160 mA.
If the battery is deeply discharged or shorted (VBAT < VBAT(SC)), the bq5105X applies IBAT(SC) current to bring the
battery voltage up to acceptable charging levels. Once the battery rises above VBAT(SC), the charge current is
regulated to IPRECHG.
Under normal conditions, the time spent in this precharge region is a very short percentage of the total charging
time and this does not affect the overall charging efficiency for very long.
8.3.4.2 Fast Charge Mode / Constant Voltage Mode
Once VBAT > VLOWV, the bq5105x enters fast charge mode (Current Regulation Phase) where charge current is
regulated using the internal MOSFETs between RECT and BAT. Once the battery voltage charges up to VBATREG, the bq5105x enters constant voltage (CV) phase and regulates battery voltage to VOREG and the charging
current is reduced.
Once IBAT falls below the termination threshold (ITERM-Th), the charger sends an EPT (Charge Complete)
notification to the TX and enters high impedance mode.
8.3.4.3 Battery Charge Current Setting Calculations
8.3.4.3.1 RILIM Calculations
The bq5105x includes a means of providing hardware overcurrent protection by means of an analog current
regulation loop. The hardware current limit provides an extra level of safety by clamping the maximum allowable
output current (for example, a current compliance). The calculation for the total RILIM resistance is as follows:
KILIM
R1 =
KILIM
t RFOD
RILIM = R1 + RFOD
IBULK =
IBULK
RILIM
(1)
Where IBULK is the programmed battery charge current during fast charge mode. When referring to the application
diagram shown in Figure 32, RILIM is the sum of RFOD and R1 (the total resistance from the ILIM pin to PGND).
8.3.4.3.2 Termination Calculations
The bq5105X includes a programmable upper termination threshold. The upper termination threshold is
calculated using Equation 2:
RTERM = KTERM * %IBULK
R
%IBULK = KTERM
TERM
(2)
The KTERM constant is specified in Electrical Characteristics as 240 Ω/%. The upper termination threshold is set
as a percentage of the charge current setting (IBULK).
For example, if RILIM is set to 314 Ω, IBULK will be 1 A (314 ÷ 314). If the upper termination threshold is desired to
be 100 mA, this would be 10% of IBULK. The RTERM resistor would then equal 2.4 kΩ (240 × 10).
Termination can be disabled by floating the TERM pin. If the TERM pin is grounded the termination function is
effectively disabled. However, due to offsets of internal comparators, termination may occur at low battery
currents.
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Feature Description (continued)
8.3.4.4 Battery-Charger Safety and JEITA Guidelines
The bq5105x continuously monitors battery temperature by measuring the voltage between the TS/CTRL pin and
PGND. A negative temperature coefficient thermistor (NTC) and an external voltage divider typically develop this
voltage. The bq5105x compares this voltage against its internal thresholds to determine if charging is allowed. To
initiate a charge cycle, the voltage on TS/CTRL pin (VTS) must be within the VT1 to VT4 thresholds. If VTS is
outside of this range, the bq5105x suspends charge and waits until the battery temperature is within the VT1 to
VT4 range. Additional information on the Temperature Sense function can be found in Internal Temperature
Sense (TS Function of the TS/CTRL Pin).
8.3.4.4.1 bq51050B and bq51051B JEITA
If VTS is within the ranges of VT1 and VT2 or VT3 and VT4, the charge current is reduced to IBULK/2. If VTS is within
the range of VT1 and VT3, the maximum charge voltage regulation is VOREG. If VTS is within the range of VT3 and
VT4, the maximum charge voltage regulation is reduced to "NEW SPEC". Figure 25 summarizes the operation.
Charge Current: IBULK
IBULK / 2
IBULK / 2
0A
Charge Voltage: VOREG
VO-J
0V
T1
(0° C)
T2
(10° C)
T3
(45° C)
T4
(60° C)
Figure 25. JEITA Compatible TS Profile for bq51050B and bq51051B
8.3.4.4.2 bq51052B Modified JEITA
The bq51052B has a modififed JEITA profile. The maximum charge current is not modified between VT1 and VT2
or between VT3 and VT4, it remains at IBULK. The maximum charge voltage is reduced to VO-J when the VTS is
between VT3 and VT4.
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Feature Description (continued)
Charge Current: IBULK
0A
Charge Voltage: VOREG
VO-J
0V
T1
(0° C)
T2
(10° C)
T3
(45° C)
T4
(60° C)
Figure 26. JEITA Compatible TS Profile for bq51052B
8.3.4.5 Input Overvoltage
If, for some condition (for example, a change in position of the equipment on the charging pad), the rectifier
voltage suddenly increases in potential, the voltage-control loop inside the bq5105x becomes active, and
prevents the output from going beyond VBAT-REG. The receiver then starts sending back error packets every 32
ms until the RECT voltage comes back to an acceptable level, and then maintains the error communication every
250 ms.
If the input voltage increases in potential beyond VOVP, the device switches off the internal FET and
communicates to the primary to bring the voltage back to VRECT-REG. In addition a proprietary voltage protection
circuit is activated by means of CCLAMP1 and CCLAMP2 that protects the device from voltages beyond the maximum
rating.
8.3.4.6 End Power Transfer Packet (WPC Header 0x02)
The WPC allows for a special command to terminate power transfer from the TX termed End Power Transfer
(EPT) packet. WPC v1.2 specifies the reasons for sending a termination packet and their data field value. In
Table 1, the CONDITION column corresponds to the stimulus causing the bq5105x device to send the
hexidecimal code in the VALUE column.
Table 1. Termination Packets
REASON
VALUE
Unknown
0x00
AD > VAD-Pres, TS/CTRL = VCTRL-HI
Charge Complete
0x01
IBAT falls below ITERM-Th during Taper mode
Internal Fault
0x02
TJ > 150°C or RILIM < RILIM-SHORT
Overtemperature
0x03
TS < VHOT, TS > VCOLD, or TS/CTRL < VCTRL-LOW
Overvoltage
0x04
Not Sent
Overcurrent
0x05
Not Sent
Battery failure
0x06
Battery is not coming out of precharge mode after Precharge time-out, or
fast charge time-out has occured.
Reconfigure
0x07
Not Sent
No Response
0x08
VRECT target does not converge
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CONDITION
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8.3.4.7 Status Output
The bq5105x provides one status output, CHG. This output is an open-drain NMOS device that is rated to 20 V.
The open-drain FET connected to the CHG pin will be turned on whenever the output (BAT) of the charger is
enabled. As a note, the output of the charger supply will not be enabled if the VRECT-REG does not converge to the
no-load target voltage.
8.3.4.8 Communication Modulator
The bq5105x provides two identical, integrated communication FETs which are connected to the pins COMM1
and COMM2. These FETs are used for modulating the secondary load current which allows bq5105x to
communicate error control and configuration information to the transmitter.There are two methods to implement
load modulation, capacitive and resistive.
Capacitive load modulation is more commonly used. Capacitive load modulation is shown in Figure 27. In this
case, a capacitor is connected from COMM1 to AC1 and from COMM2 to AC2. When the COMM switches are
closed there is effectively a 22 nF capacitor connected between AC1 and AC2. Connecting a capacitor in
between AC1 and AC2 modulates the impedance seen by the coil, which will be reflected to the primary and
interpreted by the controller as a change in current.
AC1
AC2
47 nF
47 nF
COMM1
COMM2
COMM_DRIVE
Figure 27. Capacitive Load Modulation
Figure 28 shows how the COMM pins can be used for resistive load modulation. Each COMM pin can handle at
most a 24 Ω communication resistor. Therefore, if a COMM resistor between 12 Ω and 24 Ω is required, COMM1
and COMM2 pins must be connected in parallel. bq5105x does not support a COMM resistor less than 12 Ω.
RECTIFIER
24 :
24 :
COMM1
COMM2
COMM_DRIVE
Figure 28. Resistive Load Modulation
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8.3.4.9 Adaptive Communication Limit
The Qi communication channel is established through backscatter modulation as described in the previous
sections. This type of modulation takes advantage of the loosely coupled inductor relationship between the RX
and TX coils. Essentially, the switching in-and-out of the communication capacitor or resistor adds a transient
load to the RX coil in order to modulate the TX coil voltage and current waveform (amplitude modulation). The
consequence of this technique is that a load transient (load current noise) from the mobile device has the same
signature. To provide noise immunity to the communication channel, the output load transients must be isolated
from the RX coil. The proprietary feature Adaptive Communication Limit achieves this by dynamically adjusting
the current limit of the regulator.
This can be seen in Figure 12. In this plot, an output load is limited to 400 mA during communications time. The
pulses on VRECT indicate that a communication packet event is occurring. The regulator limits the load to a
constant 400 mA and, therefore, preserves communication.
8.3.4.10 Synchronous Rectification
The bq5105x provides an integrated, self-driven synchronous rectifier that enables high-efficiency AC to DC
power conversion. The rectifier consists of an all NMOS H-Bridge driver where the back gates of the diodes are
configured to be the rectifier when the synchronous rectifier is disabled. During the initial start-up of the WPC
system the synchronous rectifier is not enabled. At this operating point, the DC rectifier voltage is provided by the
diode rectifier. Once VRECT is greater than VUVLO, half synchronous mode will be enabled until the load current
surpasses IBAT-SR. Above IBAT-SR the full synchronous rectifier stays enabled until the load current drops back
below the hysteresis level (IBAT-SRH) where half synchronous mode is re-enabled.
8.3.4.11 Internal Temperature Sense (TS Function of the TS/CTRL Pin)
The bq5105x includes a ratiometric battery temperature sense circuit. The temperature sense circuit has two
ratiometric thresholds which represent hot and cold conditions. An external temperature sensor is recommended
to provide safe operating conditions to the receiver product. This pin is best used when monitoring the battery
temperature.
The circuits in Figure 29 allow for any NTC resistor to be used with the given VHOT and VCOLD thresholds. The
thermister characteristics and threshold temperatures selected will determine which circuit is best for an
application.
VTSB
20 lQ
VTSB
R2
20 lQ
TS/CTRL
R2
TS/CTRL
R1
R1
R3
C3
C3
NTC
NTC
Figure 29. NTC Circuit Options for Safe Operation of the Wireless Receiver Power Supply
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The resistors R1 and R3 can be solved by resolving the system of equations at the desired temperature
thresholds. The two equations are:
æ R R
+ R1 ö
ç 3 NTC TCOLD
÷
çR + R
÷
R
+
3
NTC TCOLD
1 ø
è
´ 100
%VCOLD =
æ R R
+ R1 ö
3
NTC
TCOLD
ç
÷ + R2
çR + R
÷
NTC TCOLD + R1 ø
è 3
(3)
(
(
)
)
(
)
(
)
æ R (R
+ R1 ) ö
ç 3 NTC THOT
÷
çR + R
÷
R
+
3 ( NTC THOT
1 )ø
´ 100
%VHOT = è
æ R (R
ö
R
+
)
1 ÷
ç 3 NTC THOT
+ R2
çR + R
+ R1 )÷
(
3
NTC
THOT
è
ø
(4)
Where:
RNTC
TCOLD
RNTC
THOT
b
= Ro e
(1TCOLD - 1To )
b
= Ro e
(1THOT - 1To )
TCOLD and THOT are the desired temperature thresholds in degrees Kelvin. Ro is the nominal resistance at T0
(25°C) and β is the temperature coefficient of the NTC resistor. For an example solution for part number ERTJZEG103JA see the BQ5105XB NTC Calculator Tool, (SLUS629).
Where,
TCOLD = 0°C (273.15°K)
THOT = 60°C (333.15°K)
β = 3380
Ro = 10 kΩ
The plot of the percent VTSB versus temperature is shown in Figure 30:
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Figure 30. Example Solution for Panasonic Part # ERT-JZEG103JA
Figure 31 shows the periodic biasing scheme used for measuring the TS state. An internal TS_READ signal
enables the TS bias voltage for 25 ms. During this period the TS comparators are read (each comparator has a
10-ms deglitch) and appropriate action is taken based on the temperature measurement. After this 25-ms period
has elapsed the TS_READ signal goes low, which causes the TS/CTRL pin to become high impedance. During
the next 100-ms period, the TS voltage is monitored and compared to VCTRL-HI. If the TS voltage is greater than
VCTRL-HI then a secondary device is driving the TS/CTRL pin and a CTRL = 1 is detected.
240ms
Figure 31. Timing Diagram for TS Detection Circuit
8.3.4.11.1 TS/CTRL Function
The TS/CTRL pin offers three functions:
• NTC temperature monitoring
• Charge done indication
• Fault indication
When an NTC resistor is connected between the TS/CTRL pin and PGND, the NTC function is allowed to
operate. This functionality can effectively be disabled by connecting a 10 kΩ resistor from TS/CRTL to PGND. If
the TS/CTRL pin is pulled above VCTRL-HI, the RX is shut down with the indication of a charge complete
condition. If the TS/CTRL pin is pulled below VCTRL-LOW, the RX is shut down with the indication of a fault.
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8.3.4.11.2 Thermal Protection
The bq5105x includes thermal shutdown protection. If the die temperature reaches TJ-SD, the LDO is shut off to
prevent any further power dissipation. Once the temperature falls TJ-Hys below TJ-SD, operation can continue.
8.3.4.12 WPC v1.2 Compatibility
The bq5105x is a WPC v1.2 compatible device. In order to enable a Power Transmitter to monitor the power loss
across the interface as one of the possible methods to limit the temperature rise of Foreign Objects, the bq5105x
reports its Received Power to the Power Transmitter. The Received Power equals the power that is available
from the output of the Power Receiver plus any power that is lost in producing that output power. For example,
the power loss includes (but is not limited to) the power loss in the Secondary Coil and series resonant capacitor,
the power loss in the Shielding of the Power Receiver, the power loss in the rectifier, the power loss in any postregulation stage, and the eddy current loss in metal components or contacts within the Power Receiver. In the
WPC v1.2 specification, foreign object detection (FOD) is enforced, that means the bq5105x will send received
power information with known accuracy to the transmitter.
WPC v1.2 defines Received Power as “the average amount of power that the Power Receiver receives through
its Interface Surface, in the time window indicated in the Configuration Packet”.
A Receiver will be certified as WPC v1.2 only after meeting the following requirement. The device under test
(DUT) is tested on a Reference Transmitter whose transmitted power is calibrated, the receiver must send a
received power such that:
0 < (TX PWR) REF – (RX PWR out) DUT < 375 mW
(5)
This 250 mW bias ensures that system will remain interoperable.
WPC v1.2 Transmitters will be tested to see if they can detect reference Foreign Objects with a Reference
receiver. The WPC v1.2 specification allows much more accurate sensing of Foreign Objects than WPC v1.0.
A Transmitter can be certified as a WPC v1.2 only after meeting the following requirement. A Transmitter is
tested to see if it can prevent some reference Foreign Objects (disc, coin, foil) from exceeding their threshold
temperature (60°C, 80°C).
8.4 Device Functional Modes
The general modes of battery charging are described above in the Feature Description. The bq5105x devices
have several functional modes. Start-up refers to the initial power transfer and communication between the
receiver (bq5105x circuit) and the transmitter. Power transfer refers to any time that the TX and RX are
communicating and power is being delivered from the TX to the RX. Charge termination covers intentional
termination (charge complete) and unintentional termination (removal of the RX from the TX, over temperature or
other fault conditions).
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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 bq51050B is an integrated wireless power receiver and charger in a single device. The device complies with
the WPC v1.2 specifications for a wireless power receiver. When paired with a WPC v1.2 compliant transmitter, it
can provide up to 5-W of power for battery charging. There are several tools available for the design of the
system. These tools may be obtained by checking the product page at www.ti.com/product/bq51050b.
9.2 Typical Application
9.2.1 bq51050B Used as a Wireless Power Receiver and Li-Ion/Li-Pol Battery Charger
The following application discussion covers the requirements for setting up the bq51050B in a Qi-compliant
system for charging a battery.
bq5105xB
AD-EN
AD
BAT
CCOMM1
C4
COMM1
CBOOT1
D1
BOOT1
RECT
C1
AC1
TI
Wireless
Power
Transmitter
R4
C3
TX
COIL
RX
COIL
C2
PACK+
NTC
TS/CTRL
AC2
BOOT2
CBOOT2
ROS
COMM2
CHG
CCOMM2
CCLAMP2
CCLAMP1
PACK-
CLAMP2
TERM
Tri-State
CLAMP1
EN2
Bi-State
ILIM
R1
FOD
PGND
HOST
R5
RFOD
Copyright © 2016, Texas Instruments Incorporated
Figure 32. Typical Application Schematic
9.2.1.1 Design Requirements
This application is for a 4.2-V Lithium-Ion battery to be charged at 800 mA. Because this is planned for a WPC
v1.2 solution, any of the Qi-certified transmitters can be used interchangeably so no discussion of the TX is
required. To charge a 4.20-V Li-Ion battery, the bq51050B will be chosen. Each of the components from the
application drawing will be examined. Temperature sensing of the battery must be done with JEITA
specifications. An LED indicator is required to notify the user if charging is active.
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Typical Application (continued)
9.2.1.2 Detailed Design Procedure
9.2.1.2.1 Series and Parallel Resonant Capacitor Selection
Shown in Figure 33, the capacitors C1 (series) and C2 (parallel) make up the dual resonant circuit with the
receiver coil. These two capacitors must be sized correctly per the WPC v1.2 specification. Figure 33 shows the
equivalent circuit of the dual resonant circuit:
C1 (Cs)
C2 (Cd)
>•[
Figure 33. Dual Resonant Circuit with the Receiver Coil
The power receiver design requirements in volume 1 of the WPC v1.2 specification highlights in detail the sizing
requirements. To summarize, the receiver designer will be required take inductance measurements with a fixed
test fixture. The test fixture is shown in Figure 34:
Magnetic
Attractor
(example)
Interface
Surface
Secondary Coil
Shielding (optional)
Mobile
Device
Spacer
dz
Primary Shielding
Figure 34. WPC v1.2 Receiver Coil Test Fixture for the Inductance Measurement Ls’
The primary shield is to be 50 mm × 50 mm × 1 mm of Ferrite material PC44 from TDK Corp. The gap (dZ) is to
be 3.4 mm. The receiver coil, as it will be placed in the final system (for example, the back cover and battery
must be included if the system calls for this), is to be placed on top of this surface and the inductance is to be
measured at 1-V RMS and a frequency of 100 kHz. This measurement is termed Ls’. The measurement termed
Ls is the free-space inductance. Each capacitor can then be calculated using Equation 6:
1
C1 =
(2p ´ ¦ s)2 ´ L 's
æ
1 ö
C2 = ç ( ¦D ´ 2p)2 ´ L s ÷
C1 ø
è
-1
(6)
Where fS is 100 kHz +5/–10% and fD is 1 MHz ±10%. C1 must be chosen first prior to calculating C2. The quality
factor must be greater than 77 and can be determined by Equation 7:
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Typical Application (continued)
Q=
2p ´ ¦D ´ Ls
R
(7)
Where R is the DC resistance of the receiver coil. All other constants are defined above.
For this application, we will design with an inductance measurement (L) of 11 µH and an Ls' of 16 µH with a DC
resistance of 191 mΩ. Plugging Ls' into Equation 6 above, we get a value for C1 to be 158.3 nF. The range on
the capacitance is about 144 nF to 175 nF. To build the resulting value, the optimum solution is usually found
with 3 capacitors in parallel. This allows for more precise selection of values, lower effective resistance and
better thermal results. To get 158 nF, choose from standard values. In this case, the values are 68 nF, 47 nF and
39 nF for a total of 154 nF. Well in the required range. Now that C1 is chosen, the value of C2 can be calculated.
The result of this calculation is 2.3 nF. The practical solution for this is 2 capacitors, a 2.2 nF capacitor and a 100
pF capacitor. In all cases, these capacitors must have at least a 25-V rating. Solving for the quality factor (Q) this
solution shows a rating over 500.
9.2.1.2.2 COMM, CLAMP and BOOT Capacitors
For most applications, the COMM, CLAMP and BOOT capacitors will be chosen to match the Evaluation Module.
The BOOT capacitors are used to allow the internal rectifier FETs to turn on and off properly. These capacitors
are on the AC1 or AC2 lines to the Boot nodes and should have a minimum of 10-V rating. A 10-nF capacitor
with a 10-V rating is chosen.
The CLAMP capacitors are used to aid the clamping process to protect against overvoltage. Choosing a 0.47-µF
capacitor with a 25-V rating is appropriate for most applications.
The COMM capacitors are used to facilitate the communication from the RX to the TX. This selection can vary a
bit more than the BOOT and CLAMP capacitors. In general, a 22-nF capacitor is recommended. Based on the
results of testing of the communication robustness, a change to a 47-nF capacitor may be in order. The larger
the capacitor the larger the deviation will be on the coil which sends a stronger signal to the TX. This also
decreases the efficiency somewhat. In this case, choose the 22-nF capacitor with the 25-V rating.
9.2.1.2.3 Charging and Termination Current
The Design Requirements show an 800-mA charging current and an 80-mA termination current.
Setting the charge current (IBULK) is done by selecting the R1 and RFOD. Solving Equation 1 results in RILIM of 393
Ω. Setting RFOD to 200 Ω as a starting point before the FOD calibration is recommended. This leaves 205 Ω for
R1. Using standard resistor values (or resistors in series / parallel) can improve accuracy.
Setting the termination current is done with Equation 2. Because 80 mA is 10% of the IBULK (800mA), the RTERM
is calculated as (240 * 10) or 2.4 kΩ.
9.2.1.2.4 Adapter Enable
The AD pin will be tied to the external USB power source to allow for an external source to power the system.
AD_EN is tied to the gate of Q1 (CSD75205W1015). This allows the bq51050B to sense when power is applied
to the AD pin. The EN2 pin controls whether the wired source will be enabled or not. EN2 is tied to the system
host to allow it to control the use of the USB power. If wired power is enabled and present, the AD pin will
disable the BAT output and then enable Q1 through the AD_EN pin. An external charger is required to take
control of the battery charging.
9.2.1.2.5 Charge Indication and Power Capacitors
The CHG pin is open-drain. D1 and R4 are selected as a 2.1-V forward bias capable of 2 mA and a 100-Ω
current-limiting resistor.
RECT is used to smooth the internal AC to DC conversion. Two 10-µF capacitors and a 0.1-µF capacitor are
chosen. The rating is 25 V.
BAT capacitors are 1.0 µF and 0.1 µF.
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Typical Application (continued)
9.2.1.3 Application Curves
VRECT
VRECT
VBAT
VBAT
IBAT
IBAT
Figure 35. Battery Insertion During Precharge
Figure 36. Precharge to Fast-Charge Transition
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Typical Application (continued)
9.2.2 Application for Wired Charging
The application discussed below will cover the same requirements as the first example and will add a DC supply
with a secondary charger. This solution covers using a standard DC supply or a USB port as the supply.
R8
D2
bq24040
IN
OUT
R9
R6
C6
CSD75207W15
USB or
AC Adapter
Input
TS
VSS
/CHG
D3
C7
PRETERM ISET2
/PG
Q1
NC
R7
bq5105xB
C5
AD-EN
AD
BAT
CCOMM1
C4
COMM1
CBOOT1
D1
BOOT1
RECT
C1
AC1
TI
Wireless
Power
Transmitter
ISET
R4
C3
TX
COIL
RX
COIL
C2
PACK+
NTC
TS/CTRL
AC2
BOOT2
CBOOT2
ROS
COMM2
CCOMM2
CCLAMP2
CCLAMP1
CLAMP2
TERM
CLAMP1
EN2
ILIM
R1
PACK-
CHG
FOD
PGND
Tri-State
Bi-State
HOST
R5
RFOD
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Figure 37. bq51050B Wireless Power Receiver and Wired Charger
9.2.2.1 Design Requirements
The requirements for this solution are identical to the first application so all common components are identical.
This solution adds a wired charger and a blocking back-back FET (Q1).
The addition of a wired charger is simply enabled. The AD pin on the bq5105x is tied to the input of the DC
supply. When the bq5105x senses a voltage greater than VAD-Pres on the AD pin, the BAT pin will be disabled
(high impedance). Once the BAT pin is disabled, the AD_EN pin will transition and enable Q1. If wireless power
is not present, the functionality of AD and AD_EN remains and wired charging can take place.
9.2.2.2 Detailed Design Procedure
9.2.2.2.1 Blocking Back-Back FET
Q1 is recommended to eliminate the potential for both wired and wireless systems to drive current to the
simultaneously. The charge current and DC voltage level will set up parmerters for the blocking FET. The
requirements for this system are 1 A for the wired charger and 5 V DC. The CSD75207W15 is chosen for its low
RON and small size.
The wired charger in this solution is the bq24040. See the bq24040 datasheet (SLUS941) for specific component
selection.
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bq51050B, bq51051B, bq51052B
www.ti.com
SLUSB42F – JULY 2012 – REVISED JUNE 2017
10 Power Supply Recommendations
The bq51050B requires a Qi-compatible transmitter as its power supply.
11 Layout
11.1 Layout Guidelines
•
•
•
•
•
•
•
Keep the trace resistance as low as possible on AC1, AC2, and BAT.
Detection and resonant capacitors need to be as close to the device as possible.
COMM, CLAMP, and BOOT capacitors need to be placed as close to the device as possible.
Via interconnect on PGND net is critical for appropriate signal integrity and proper thermal performance.
High frequency bypass capacitors need to be placed close to RECT and OUT pins.
ILIM and FOD resistors are important signal paths and the loops in those paths to PGND must be minimized.
For the RHL package, connect the thermal pad to ground to help dissipate heat.
Signal and sensing traces are the most sensitive to noise; the sensing signal amplitudes are usually
measured in mV, which is comparable to the noise amplitude. Make sure that these traces are not being
interfered by the noisy and power traces. AC1, AC2, BOOT1, BOOT2, COMM1, and COMM2 are the main
source of noise in the board. These traces should be shielded from other components in the board. It is
usually preferred to have a ground copper area placed underneath these traces to provide additional
shielding. Also, make sure they do not interfere with the signal and sensing traces. The PCB should have a
ground plane (return) connected directly to the return of all components through vias (two vias per capacitor
for power-stage capacitors, one via per capacitor for small-signal components).
For a 1-A fast charge current application, the current rating for each net is as follows:
• AC1 = AC2 = 1.2 A
• OUT = 1 A
• RECT = 100 mA (RMS)
• COMMx = 300 mA
• CLAMPx = 500 mA
• All others can be rated for 10 mA or less
11.2 Layout Example
CLAMP2
capacitor
BOOT2
TS
/C
AC2
2
M
M
CO
BAT
BOOT2
capacitor
L
TR
ILIM
EN2
PGND
TERM
AC1-AC2 capacitors
AD
/CHG
CLAMP2
capacitor
COMM1
capacitor
BAT
BOOT1
capacitor
BOOT1
AC1 Series capacitors
AC1
COMM1
BAT capacitors
Figure 38. bq5105x Layout Example
Copyright © 2012–2017, Texas Instruments Incorporated
Product Folder Links: bq51050B bq51051B bq51052B
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33
bq51050B, bq51051B, bq51052B
SLUSB42F – JULY 2012 – REVISED JUNE 2017
www.ti.com
12 Device and Documentation Support
12.1 Documentation Support
12.1.1 Related Documentation
For related documentation, see the following:
bq2404x 1A, Single-Input, Single Cell Li-Ion and Li-Pol Battery Charger With Auto Start, SLUS941
12.2 Related Links
The table below lists quick access links. Categories include technical documents, support and community
resources, tools and software, and quick access to sample or buy.
Table 2. Related Links
PARTS
PRODUCT FOLDER
SAMPLE & BUY
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
bq51050B
Click here
Click here
Click here
Click here
Click here
bq51051B
Click here
Click here
Click here
Click here
Click here
bq51052B
Click here
Click here
Click here
Click here
Click here
12.3 Receiving Notification of Documentation Updates
To receive notification of documentation updates — go to the product folder for your device on ti.com. In the
upper right-hand corner, click the Alert me button to register and receive a weekly digest of product information
that has changed (if any). For change details, check the revision history of any revised document.
12.4 Community Resources
The following links connect to TI community resources. Linked contents are 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.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
12.5 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
12.6 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
12.7 Glossary
SLYZ022 — 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.
34
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Copyright © 2012–2017, Texas Instruments Incorporated
Product Folder Links: bq51050B bq51051B bq51052B
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
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)
(4/5)
(6)
BQ51050BRHLR
ACTIVE
VQFN
RHL
20
3000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
0 to 125
BQ51050B
BQ51050BRHLT
ACTIVE
VQFN
RHL
20
250
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
0 to 125
BQ51050B
BQ51050BYFPR
ACTIVE
DSBGA
YFP
28
3000
RoHS & Green
SNAGCU
Level-1-260C-UNLIM
0 to 125
BQ51050B
BQ51050BYFPT
ACTIVE
DSBGA
YFP
28
250
RoHS & Green
SNAGCU
Level-1-260C-UNLIM
0 to 125
BQ51050B
BQ51051BRHLR
ACTIVE
VQFN
RHL
20
3000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
0 to 125
BQ51051B
BQ51051BRHLT
ACTIVE
VQFN
RHL
20
250
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
0 to 125
BQ51051B
BQ51051BYFPR
ACTIVE
DSBGA
YFP
28
3000
RoHS & Green
SNAGCU
Level-1-260C-UNLIM
0 to 125
BQ51051B
BQ51051BYFPT
ACTIVE
DSBGA
YFP
28
250
RoHS & Green
SNAGCU
Level-1-260C-UNLIM
0 to 125
BQ51051B
BQ51052BYFPR
ACTIVE
DSBGA
YFP
28
3000
RoHS & Green
SNAGCU
Level-1-260C-UNLIM
0 to 125
BQ51052B
BQ51052BYFPT
ACTIVE
DSBGA
YFP
28
250
RoHS & Green
SNAGCU
Level-1-260C-UNLIM
0 to 125
BQ51052B
(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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