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bq500414Q
SLUSBE4B – JANUARY 2014 – REVISED JUNE 2014
bq500414Q Automotive, Free Positioning,
Qi Compliant Wireless Power Transmitter Manager
1 Features
3 Description
•
The bq500414Q is an AEC-Q100 qualified freepositioning digital wireless power controller designed
for automotive applications. It integrates all functions
required to control wireless power transfer to a WPC
compliant receiver. It is WPC v1.1 ready and
designed for 12-V systems; however, the bq500414Q
is applicable to other supply voltages. The
bq500414Q pings the surrounding environment for
WPC compliant devices to be powered. Once a WPC
compliant device is detected, the bq500414Q reads
the packet feedback from the powered device and
manages the power transfer. A charging area of 70mm x 20-mm provides flexible receiver placement on
a transmitter pad. The bq500414Q supports both
Parasitic Metal Object Detection (PMOD) and Foreign
Object Detection (FOD) by continuously monitoring
the transmitted and received power of the system,
protecting the device from over heating. Should any
abnormal condition develop during power transfer,
the bq500414Q handles it and provides fault indicator
outputs. Comprehensive protection features provide a
robust design to protect the system in all receiver
placements.
1
•
•
•
•
•
•
•
•
Expanded Free Positioning Using Three Coil
Transmit Array
AEC-Q100 Qualified for Automotive Applications
Conforms to Wireless Power Consortium (WPC)
A6 Transmitter Type Specification
I2C Interface to Enable Control and
Communication With Host Controllers, that is
Read Tx and Rx Stats, Start Tx, and Shift Tx
Operating Frequency
WPC v1.1 Compliant, Including Improved Foreign
Object Detection (FOD) Method
Enhanced Parasitic Metal Object Detection
(PMOD) for WPC v1.0 Receivers Protection
Digital Demodulation Reduces Components
Over-Current Protection
LED Indication of Charging State and Fault Status
2 Applications
•
•
WPC 1.1 Wireless Chargers:
– In Cars and Other Vehicle Accessories
– Qi-Certified Smart Phones and Other
Handhelds
– Industrial and Medical Applications
See www.ti.com/wirelesspower for More
Information on TI's Wireless Charging Solutions
The bq500414Q is available in an area saving 48-pin,
7-mm × 7-mm VQFN package and operates over a
temperature range from –40°C to 85°C.
Device Information(1)
DEVICE NAME
PACKAGE
bq500414Q
VQFN (48)
BODY SIZE
7 mm × 7 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
4 Simplified Diagram
Efficiency Versus System Output Power With A6 Tx Coil
6-16V
80
12V
No SEPIC Converter
SEPIC
70
ISense
60
HB
Power
Stage
2
IC
CAN or LIN
Controller
BQ500414Q
HB
Power
Stage
Efficiency (%)
3.3V
SW
50
With SEPIC Converter
40
30
20
HB
Power
Stage
Without SEPIC
10
With SEPIC
0
Feedback
Multiplexer
0
1
2
3
Output Power (W)
4
5
C002
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.
bq500414Q
SLUSBE4B – JANUARY 2014 – REVISED JUNE 2014
www.ti.com
Table of Contents
1
2
3
4
5
6
7
8
Features ..................................................................
Applications ...........................................................
Description .............................................................
Simplified Diagram ................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
1
2
3
5
7.1
7.2
7.3
7.4
7.5
7.6
5
5
6
6
7
8
Absolute Maximum Ratings .....................................
Handling Ratings.......................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
Typical Characteristics ..............................................
Detailed Description .............................................. 9
8.1 Overview ................................................................... 9
8.2 Functional Block Diagram ......................................... 9
8.3 Feature Description................................................. 10
8.4 Device Functional Modes........................................ 17
9
Applications and Implementation ...................... 19
9.1 Application Information............................................ 19
9.2 Typical Application .................................................. 19
10 Power Supply Recommendations ..................... 23
11 Layout................................................................... 23
11.1 Layout Guidelines ................................................. 23
11.2 Layout Example .................................................... 24
12 Device and Documentation Support ................. 27
12.1
12.2
12.3
12.4
Device Support......................................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
27
27
27
27
13 Mechanical, Packaging, and Orderable
Information ........................................................... 27
5 Revision History
Changes from Original (January 2014) to Revision A
•
Page
Updated preview document to full version. ............................................................................................................................ 1
Changes from Revision A (March 2014) to Revision B
Page
•
Deleted all references to the Wireless Power Consortium (WPC) A19 and A21 Transmitter Type Specifications. .............. 1
•
Changed Enhanced Parasitic Metal Object Detection (PMOD) bullet. ................................................................................. 1
•
Changed bq500414Q description. .......................................................................................................................................... 1
•
Changed Pin Functions Table EMI_SHIELD pin from O to I. ............................................................................................... 4
•
Changed Pin Functions Table COIL_SEL pin from I/O to I.................................................................................................... 4
•
Changed JEDEC document JEP157 Handling Ratings note. ................................................................................................ 5
•
Changed Foreign Object Detection (FOD) and Parasitic Metal Object Detect (PMOD) Calibration description. ............... 13
•
Changed Over-Current Protection description. .................................................................................................................... 16
•
Changed Over-Voltage Protection section. .......................................................................................................................... 16
2
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SLUSBE4B – JANUARY 2014 – REVISED JUNE 2014
6 Pin Configuration and Functions
ADCREF
GND
Unused
V_SENSE
LED_MODE
LOSS_THR
I_SENSE
RESERVED
COMM_B-
COMM_B+
COMM_A-
COMM_A+
48
47
46
45
44
43
42
41
40
39
38
37
RGZ (VQFN) PACKAGE
(TOP VIEW)
COIL_PEAK
1
36
GND
T_SENSE
2
35
BPCAP
Unused
3
34
V33A
Unused
4
33
V33D
RESET
5
32
GND
PMOD
6
31
RESERVED
bq500414Q
LED_A
7
30
RESERVED
LED_B
8
29
RESERVED
LED_C
9
28
RESERVED
PMB_CLK
10
27
RESERVED
PMB_DATA
11
26
RESERVED
25
COIL_SEL
49
13
14
15
16
17
18
19
20
21
22
23
24
Unused
Coil 1.1
Coil 1.2
Coil 1.3
EN_PWR
RESERVED
RESERVED
EMI_SHIELD
FOD_CAL
BUZ_AC
BUZ_DC
12
FOD
DPWM_A
GND
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Pin Functions
PIN
NAME
NUMBER
COIL_PEAK
1
T_SENSE
2
Unused
3
Unused
4
RESET
PMOD
I/O
DESCRIPTION
I
Input from peak detect circuit
I
Sensor input. Device shuts down when below 1 V. If not used, keep above 1 V by simply
connecting to 3.3-V supply
I
This pin can be either connected to GND or left open. Connecting to GND can improve layout
grounding
I
This pin can be either connected to GND or left open. Connecting to GND can improve layout
grounding
5
I
Device reset. Use 10-kΩ to 100-kΩ pull-up resistor to 3.3-V supply
6
O
Select for PMOD threshold
LED_A
7
O
Connect to a LED via 470-Ω resistor for status indication. Typically GREEN
LED_B
8
O
Connect to a LED via 470-Ω resistor for status indication. Typically RED
LED_C
9
O
Connect to a LED via 470-Ω resistor for status indication. Typically YELLOW
PMB_CLK
10
I/O
10-kΩ pull-up resistor to 3.3-V supply. I2C Clock
PMB_DATA
11
I/O
10-kΩ pull-up resistor to 3.3-V supply. I2C Data
DPWM_A
12
O
PWM Output to half bridge driver. Switching dead times must be externally generated
FOD
13
O
Select for FOD threshold
Unused
14
O
Reserved, leave this pin open
COIL 1.1
15
O
Enables the first coil drive train and COMM signal selector
COIL 1.2
16
O
Enables the second coil drive train and COMM signal selector
COIL 1.3
17
O
Enables the third coil drive train and COMM signal selector
EN_PWR
18
I/O
Enable signal to the front end converter. Select the active or passive wake-up state
RESERVED
19
O
Reserved, leave this pin open
RESERVED
20
I
Reserved, connect to GND
EMI_SHIELD
21
I
Connect to 3.3-V supply to indicate EMI shield is in use. If not, connect this pin to GND
FOD_CAL
22
O
FOD Calibration
BUZ_AC
23
O
AC buzzer output. A 400-ms, 4-kHz AC pulse train when charging begins
BUZ_DC
24
O
DC buzzer output. A 400-ms DC pulse when charging begins. This could also be connected to
an LED via 470-Ω resistor
COIL_SEL
25
I
Coil type select. Connect to GND for A6 typle Tx
RESERVED
26
I/O
Reserved, connect to GND
RESERVED
27
I/O
Reserved, leave this pin open
RESERVED
28
I/O
Reserved, leave this pin open
RESERVED
29
I/O
Reserved, leave this pin open
RESERVED
30
I/O
Reserved, leave this pin open
RESERVED
31
I/O
Reserved, connect 10-kΩ pull-down resistor to GND. Do not leave open
GND
32
—
GND
V33D
33
—
Digital Core 3.3-V supply. Be sure to decouple with bypass capacitors as close to the part as
possible
V33A
34
—
Analog 3.3-V supply. This pin can be derived from V33D supply, decouple with 22-Ω resistor
and additional bypass capacitors
BPCAP
35
—
Bypass capacitor for internal 1.8-V core regulator. Connect bypass capacitors to GND and to
3.3-V
GND
36
—
GND
COMM_A+
37
I
Digital demodulation noninverting input A, connect parallel to input B+
COMM_A-
38
I
Digital demodulation inverting input A, connect parallel to input B-
COMM_B+
39
I
Digital demodulation noninverting input B, connect parallel to input A+
COMM_B-
40
I
Digital demodulation inverting input B, connect parallel to input A-
RESERVED
41
I
Reserved, leave this pin open
4
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Pin Functions (continued)
PIN
NAME
NUMBER
I/O
DESCRIPTION
I_SENSE
42
I
Transmitter input current, used for parasitic loss calculations. Use 40-mΩ sense resistor and A
= 50 gain current sense amp
LOSS_THR
43
I
Input to program FOD/PMOD thresholds and FOD_CAL correction
LED_MODE
44
I
LED Mode Select
V_SENSE
45
I
Transmitter power train input voltage, used for FOD and Loss calculations.
Unused
46
I
This pin can be either connected to GND or left open. Connecting to GND can improve layout
grounding
GND
47
—
ADCREF
48
I
EPAD
49
—
GND
External reference voltage input. Connect this input to GND.
Flood with copper GND plane and stitch vias to PCB internal GND plane
7 Specifications
7.1 Absolute Maximum Ratings (1)
over operating free-air temperature range (unless otherwise noted)
MIN
MAX
Voltage applied at V33D to DGND
–0.3
3.6
Voltage applied at V33A to AGND
–0.3
3.6
Voltage applied to any pin (2)
–0.3
3.6
(1)
(2)
UNIT
V
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 referenced to GND.
7.2 Handling Ratings
Tstg
Storage temperature range
V(ESD)
(1)
(2)
(3)
(1)
Human-Body Model (HBM) (2)
Charged-Device Model (CDM) (3)
MIN
MAX
–40
150
UNIT
°C
2
2
kV
750
750
kV
Electrostatic discharge (ESD) to measure device sensitivity and immunity to damage caused by assembly line electrostatic discharges in
to the device.
Level listed above is the passing level per ANSI, ESDA, and JEDEC JS-001. JEDEC document JEP155 states that 500-V HBM allows
safe manufacturing with a standard ESD control process.
Level listed above is the passing level per EIA-JEDEC JESD22-C101. JEDEC document JEP157 states that 250-V CDM allows
manufacturing without risk of damaging the device with a standard ESD control process.
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7.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
NOM
MAX
3.3
3.6
V
Supply voltage during operation, V33D, V33A
3.0
TA
Operating free-air temperature range
–40
TJ
Junction temperature
85
85
UNIT
V
°C
7.4 Thermal Information
bq500414Q
THERMAL METRIC (1)
RGZ
48 PINS
RθJA
Junction-to-ambient thermal resistance
27.1
RθJC(top)
Junction-to-case (top) thermal resistance
12.9
RθJB
Junction-to-board thermal resistance
4.3
ψJT
Junction-to-top characterization parameter
0.2
ψJB
Junction-to-board characterization parameter
4.3
RθJC(bot)
Junction-to-case (bottom) thermal resistance
0.6
(1)
6
UNIT
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
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7.5 Electrical Characteristics
over operating free-air temperature range (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
NOM
MAX
V33A = 3.3 V
8
15
V33D = 3.3 V
44
55
V33D = V33A = 3.3 V
52
60
3.3
3.6
4
4.6
UNIT
SUPPLY CURRENT
IV33A
IV33D
Supply current
ITotal
mA
INTERNAL REGULATOR CONTROLLER INPUTS/OUTPUTS
V33
3.3-V linear regulator
V33FB
3.3-V linear regulator feedback
IV33FB
Series pass base drive
Beta
Series NPN pass device
Emitter of NPN transistor
3.25
VIN = 12 V; current into V33FB pin
10
V
mA
40
EXTERNALLY SUPPLIED 3.3 V POWER
V33D
Digital 3.3-V power
TA = 25°C
3
3.6
V33A
Analog 3.3-V power
TA = 25°C
3
3.6
V33Slew
3.3-V slew rate
3.3-V slew rate between 2.3 V and 2.9 V,
V33A = V33D
0.25
V
V/ms
DIGITAL DEMODULATION INPUTS: COMM_A+, COMM_A-, COMM_B+, COMM_BVCM
Common mode voltage each pin
COMM+,
COMM-
–0.15
Modulation voltage digital resolution
REA
Input Impedance
Ground reference
0.5
IOFFSET
Input offset current
1-kΩ source impedance
–5
1.631
1
1.5
V
mV
3
MΩ
5
µA
0.36
V
ANALOG INPUTS: V_IN, V_SENSE, I_SENSE, T_SENSE, LED_MODE, LOSS_THR
VADC_OPEN
Voltage indicating open pin
LED_MODE, LOSS_THR open
VADC_SHORT
Voltage indicating pin shorted to GND
LED_MODE, LOSS_THR shorted to ground
VADC_RANGE
Measurement range for voltage monitoring
ALL ANALOG INPUTS
INL
ADC integral nonlinearity
Ilkg
Input leakage current
3 V applied to pin
RIN
Input impedance
Ground reference
CIN
Input capacitance
2.37
0
–2.5
2.5
2.5
100
8
mV
nA
MΩ
10
pF
DIGITAL INPUTS/OUTPUTS
DGND1
+ 0.25
VOL
Low-level output voltage
IOL = 6 mA , V33D = 3 V
VOH
High-level output voltage
IOH = –6 mA , V33D = 3 V
VIH
High-level input voltage
V33D = 3 V
VIL
Low-level input voltage
V33D = 3.5 V
IOH(MAX)
Output high source current
4
IOL(MAX)
Output low sink current
4
V33D
– 0.6 V
2.1
V
3.6
1.4
mA
SYSTEM PERFORMANCE
VRESET
Voltage where device comes out of reset
V33D pin
tRESET
Pulse width needed for reset
RESET pin
fSW
Switching Frequency
tdetect
Time to detect presence of device requesting
power
2.4
2
120
205
kHz
0.5
s
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µs
7
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7.6 Typical Characteristics
Figure 1. Typical PWM Signal
Figure 3. Tx Coil and Rx Communication Signals
with Rx No Load
8
Figure 2. Typical Tx Coil and Rx Communication Signals
Figure 4. Tx Coil and Rx Communication Signals
with Rx 5W Load
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8 Detailed Description
8.1 Overview
The principle of wireless power transfer is simply an open cored transformer consisting of transmitter (Tx) and
receiver (Rx) coils. The transmitter coil and electronics are typically built into a charger pad and the receiver coil
and electronics are typically built into a portable device, such as a cell-phone.
When the receiver coil is positioned on the transmitter coil, magnetic coupling occurs once the transmitter coil is
driven. The flux is coupled into the secondary coil which induces a voltage and current flows. The secondary
voltage is rectified, and power can be transferred effectively to a load, wirelessly. Power transfer can be
managed through any of various familiar closed-loop control schemes.
The bq500414Q sends an analog ping to detect the presence of a receiver on the pad. An external enable trigger
or proximity detector can also be used to provide the means of detecting the presence of a receiver. The detector
can output an enable signal to the regulator supplying the bq500414Q and the device powers up, or the enable
signal can start the Tx via I2C command. Once the bq500414Q is active, it pings the three coils sequentially to
detect and power up the Rx. Once the Rx is powered up, it sends the communication packages to the Tx. The
package information can be fetched by the Tx through demodulating the COMM feedback signal, which is a
scaled version of primary coil voltage. The COMM feedback signal is multiplexed through analog switches and is
synchronized to the coil being driven. To select the best coil match, the bq500414Q looks for the strongest
COMM signal. Note that only one coil is driven at a time. The driven coil is tolerant of slight misalignment of the
Rx while power is being transferred. Actually displacing the Rx to an adjacent coil while charging is allowable, the
sequential ping sequence and detection to determine the best matching coil to drive continues to repeat.
bq500414Q provides I2C interface to support some read and write commands, which can also be used to start
the Tx and temporarily shift the Tx operating frequency.
8.2 Functional Block Diagram
6
bq500414Q
LED_A
8
LED_B
9
LED_C
22 FOD_CAL
Digital I/O
COMM_A+ 37
PMOD
7
25 COIL_SEL
COMM_A- 38
COMM_B+ 39
18 ~ EN_PWR
Digital
Demodulation
13 FOD
21 EMI_SHIELD
COMM_B- 40
12 DPWM-A
15 COIL 1.1
Controller
PWM
16 COIL 1.2
COIL_PEAK
1
17 COIL 1.3
V_SENSE 45
I_SENSE 42
T_SENSE
2
12-bit
ADC
23 BUZ_AC
Buzzer
Control
24 BUZ_DC
LOSS_THR 43
LED_MODE 44
POR
11 PMB_DATA
I2C
10 PMB_CLK
5
RESET
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8.3 Feature Description
8.3.1 A6 Coil Specification
bq500414Q supports WPC A6 transmitter type. The coil and matching capacitor specification for the A6
transmitter has been established by WPC standard. This is fixed and cannot be changed on the transmitter side.
The bq500414Q is primarily intended to drive a 3 coil array but it can also be used to drive a single coil or two
coils. For single coil operation, the other coils and associated electronics are simply omitted.
Schematics and BOM can be found on the product folder at www.ti.com.
For a current list of coil vendors please see:
• bqTESLA Transmitter Coil Vendors, SLUA649
8.3.2 EMI Shield
TI recommends using a PCB based Electromagnetic Interference (EMI) shield to improve the EMI performance.
The shield needs to be grounded. Pin 21 is used to indicate if EMI shield is in use. See product folder at
www.ti.com for additional information on reference designs and applications.
8.3.3
I2C Interface
The bq500414Q supports read and write commands via I2C, as well as firmware upgrade. This could help the
host controller monitor system information, control output power, and temporarily shift the Tx operating
frequency.
The slave address assigned to the bq500414Q has been hardcoded to 20 (decimal). The hardware can support
100-kHz, 400-kHz, or 1-MHz I2C operation. Contact Texas Instruments for additional information on I2C interface.
8.3.4 Active or Passive Wake-up State
At power up, the bq500414Q will read EN_PWR pin voltage. If it is low, the bq500414Q device will be in active
wake-up state. It will send a analog ping to detect if a compatible Rx is present and then sends a digital ping to
power up the Rx. If the EN_PWR pin voltage is high, the bq500414Q will be in a passive wake-up state and
considers that the SHUTDOWN command is issued. It will not send any analog ping or digital ping to detect the
presence Rx, until the SHUTDOWN command is disabled through I2C. Once the SHUTDOWN command is
disabled, the bq500414Q device will be in active wake-up state and send the analog ping to detect the Rx. At the
same time, it drives EN_PWR pin LOW to enable the SEPIC converter. This feature enables the use of a
customer defined proximity sensor.
8.3.5 Smart Key or Immobilizer Handling
The host controller may temporarily shift the bq500414Q operating frequency via I2C, when a smart key or an
immobilizer is being used to avoid the interference.
10
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Feature Description (continued)
8.3.6 Option Select Pins
There are four option select pins (pin 18 ~EN_PWR, pin 21 EMI_SHIELD, pin 43 LOSS_THR and pin 44
LED_MODE) on the bq500414Q. All the pin voltages will be read by bq500414Q at power up.
• Pin 18 is used to indicate if the Tx should be go into active or passive wake-up state. This pin is a logic input
that can be tied to 3.3-V or GND for indication. This pin is also the active LOW enable signal to the SEPIC.
• Pin 21 is used to indicate if EMI shield is in use. This pin is a logic input that can be tied to 3.3-V or GND for
indication.
• Pin 43 is used to program the Loss Threshold and FOD Calibration.
• Pin 44 is used to select the LED mode of the device. At power up, a bias current is applied to pins
LED_MODE and LOSS_THR and the resulting voltage is measured in order to identify the value of the
attached programming resistor. For LED_MODE, the selected bin determines the LED behavior based on
Table 1. For the LOSS_THR, the selected bin sets a threshold based on Table 2. See Foreign Object
Detection (FOD) and Parasitic Metal Object Detect (PMOD) Calibration section for more information.
LED_MODE
44
Resistors
to set
options
LOSS_THR
To 12-bit ADC
43
FOD
PMOD
FOD_CAL
13
6
22
Figure 5. Pin 43 LOSS_THR and Pin 44 LED_MODE Connections
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Feature Description (continued)
8.3.7 LED Modes
The bq500414Q can directly drive three LED outputs (pin 7, pin 8, and pin 9) through a simple current limit
resistor (typically 470-Ω), based on the mode selected. The three current limit resistors can be individually
adjusted to tune or match the brightness of the LEDs. Do not exceed the maximum output current rating of the
device.
The selection resistor, connected between pin 44 and GND, selects one of the desired LED indication schemes
presented in Table 1.
Table 1. LED Modes
LED
CONTROL
OPTION
LED
SELECTION
RESISTOR
X
< 36.5 kΩ
OPERATIONAL STATES
DESCRIPTION
LED
STANDBY
POWER
TRANSFER
CHARGE
COMPLETE
FAULT
FOD Warning
-
-
-
-
-
LED1, green
Off
Blink slow (1)
On
Off
Off
LED2, red
Off
Off
Off
On
Blink fast (2)
LED1, green
Reserved, do not use
LED2, red
LED3, amber
1
2
3 (3)
4
5
6
7
(1)
(2)
(3)
12
42.2 kΩ
48.7 kΩ
56.2 kΩ
64.9 kΩ
75 kΩ
86.6 kΩ
100 kΩ
Choice number 1
Choice number 2
Choice number 3
Choice number 4
Choice number 5
Choice number 6
Choice number 7
LED3, amber
-
-
-
-
-
LED1, green
On
Blink slow (1)
On
Off
Off
Blink fast (2)
LED2, red
On
Off
Off
On
LED3, amber
-
-
-
-
-
LED1, green
Off
On
Off
Blink fast (2)
On
-
LED2, red
-
-
-
-
LED3, amber
-
-
-
-
-
LED1, green
Off
On
Off
Off
Off
LED2, red
Off
Off
Off
On
Blink fast (2)
LED3, amber
-
-
-
-
-
LED1, green
Off
Off
On
Off
Off
LED2, red
Off
On
Off
Off
On
LED3, amber
Off
Off
Off
Blink slow (1)
Off
LED1, green
Off
Blink slow (1)
On
Off
Off
LED2, red
Off
Off
Off
On
Blink fast (2)
LED3, amber
Off
Off
Off
Off
Off
LED1, green
Off
Blink slow (1)
Off
Off
Off
LED2, red
Off
Off
On
Off
Off
LED3, amber
Off
Off
Off
On
Blink fast (2)
Blink slow = 0.625 Hz
Blink fast = 2.5 Hz
The indication of the shutdown after an Negative Temperature Coefficient (NTC) event may experience a delay in the rapid LED blinking
even though the power transfer has been disabled. The indication delay may persist up to as long as the entire NTC FAULT holdoff
time.
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8.3.8 Foreign Object Detection (FOD) and Parasitic Metal Object Detect (PMOD) Calibration
The bq500414Q supports improved FOD (WPC v1.1) and enhanced PMOD (WPC v1.0) features. Continuously
monitoring input power, known losses, and the value of power reported by the Rx device being charged, the
bq500414Q can estimate how much power is unaccounted for and presumed lost due to metal objects placed in
the wireless power transfer path. If this unexpected loss exceeds the threshold set by the FOD or PMOD
resistors, a fault is indicated and power transfer is halted. Whether the FOD or the PMOD algorithm is used is
determined by the ID packet of the receiver being charged. The ultimate goal of the FOD feature is to protect
misplaced metal objects from becoming hot. Reducing the loss threshold and making the system too sensitive
will lead to false trips and a bad user experience. Find the balance which best suits the application. If the
application requires disabling one function or the other (or both), it is possible by leaving the respective
FOD/PMOD pin open. For example, to selectively disable the PMOD function, PMOD (pin 6) should be left open.
NOTE
Disabling FOD results in a Tx solution that is not WPC 1.1 Compliant
Resistors of 1% tolerance should be used for a reliable selection of the desired threshold. The FOD and PMOD
resistors (pin 13 and pin 6) program the permitted power loss for the FOD and PMOD algorithms respectively.
The FOD_CAL resistor (pin 22), can be used to compensate for any load dependent effect on the power loss.
Using a calibrated FOD reference receiver with no foreign objects present, the FOD_CAL resistor should be
selected such that the calculated loss across the load range is substantially constant (within ~100-mW). After
correcting for the load dependence, the FOD and PMOD thresholds should be re-set above the resulting average
by approximately 400-mW in order for the transmitter to satisfy the WPC requirements on tolerated heating.
Contact Texas Instruments for the Tx Tuning Tool to set appropriate FOD, PMOD, and FOD_CAL resistor values
for your design.
Table 2. Option Select Bins
BIN NUMBER
RESISTANCE (kΩ)
LOSS THRESHOLD
(mW)
0
< 36.5
250
1
42.2
300
2
48.7
350
3
56.2
400
4
64.9
450
5
75.0
500
6
86.6
550
7
100
600
8
115
650
9
133
700
10
154
750
11
178
800
12
205
850
13
> 237
Feature Disabled
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8.3.9 Shut Down via External Thermal Sensor or Trigger
Typical applications of the bq500414Q do not require additional thermal protection. This shutdown feature is
provided for enhanced applications and is not limited to thermal shutdown. The key parameter is the 1.0-V
threshold on pin 2 T_SENSE. Voltage below 1.0-V on pin 2 causes the device to shut down.
The application of thermal monitoring via a Negative Temperature Coefficient (NTC) sensor, for example, is
straightforward. The NTC forms the lower leg of a temperature dependant voltage divider. The NTC leads are
connected to the bq500414Q device, pin 2 and GND. The threshold on pin 2 is set to 1.0 V, below which the
system shuts down and a fault is indicated (depending on LED mode chosen).
To
1.
2.
3.
4.
implement this feature follow these steps:
Consult the NTC datasheet and find the resistence vs temperature curve.
Determine the actual temperature where the NTC will be placed by using a thermal probe.
Read the NTC resistance at that temperature in the NTC datasheet, that is R_NTC.
Use the following formula to determine the upper leg resistor (R_Setpoint):
R _ Setpoint = 2.3 ´ R _ NTC
(1)
The system restores normal operation after approximately five minutes or if the receiver is removed. If the feature
is not used, this pin must be pulled high.
NOTE
Pin 2 T_SENSE must always be terminated, otherwise erratic behavior may occur.
3V3_VCC
Optional
Temperature
Sensor
R_Setpoint
T_SENSE
NTC
2
AGND
AGND
Figure 6. Negative Temperature Coefficient (NTC) Application
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8.3.10 Fault Handling and Indication
The following is a table of End Power Transfer (EPT) packet responses, fault conditions, and the duration how
long the condition lasts until a retry in attempted. The LED mode selected determines how the LED indicates the
condition or fault.
Table 3. Fault Handling and Indication
CONDITION
DURATION (1)
(BEFORE RETRY)
EPT-00
Immediate (2)
Unknown
EPT-01
5 seconds
Charge complete
EPT-02
Infinite
Internal fault
EPT-03
5 minutes
Over temperature
EPT-04
Immediate (2)
Over voltage
EPT-05
Immediate (2)
Over current
EPT-06
Infinite
Battery failure
EPT-07
Not applicable
Reconfiguration
EPT-08
Immediate (2)
No response
OVP (over voltage)
Immediate (2)
OC (over current)
1 minute
NTC (external sensor)
5 minutes
PMOD/FOD warning
12 seconds
PMOD/FOD
5 minutes
(1)
(2)
HANDLING
10 seconds LED only,
2 seconds LED +
buzzer
After a FAULT, the magnetic field is re-characterized in order to
improve the ability to detect the removal of the at-fault receiver. If the
receiver is removed in the first second immediately following the
detection of this fault (before the re-characterization is complete), the
field corresponding to an empty pad may be associated with the
faulty receiver and the LED indication may continue to indicate a
fault state even though no receiver is present. This indication will
persist until either the HOLDOFF time expires or a new receiver
disturbs the field, at which time normal operation, with proper LED
indication, will be resumed.
Immediate is less than 1 second.
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8.3.11 Power Transfer Start Signal
The bq500414Q features two signal outputs to indicate that power transfer has begun. Pin 23 BUZ_AC outputs a
400-ms duration, 4-kHz square wave for driving low cost AC type ceramic buzzers. Pin 24 BUZ_DC outputs logic
high, also for 400-ms, which is suitable for DC type buzzers with built-in tone generators, or as a trigger for any
type of customized indication scheme. Do not exceed 4-mA loading from either of these pins which is more than
adequate for small signaling and actuation. If not used, these pins should be left open.
8.3.12 Power-On Reset
The bq500414Q has an integrated Power-On Reset (POR) circuit which monitors the supply voltage and handles
the correct device startup sequence. Additional supply voltage supervisor or reset circuits are not needed.
8.3.13 External Reset, RESET Pin
The bq500414Q can be forced into a reset state by an external circuit connected to the RESET pin. A logic low
voltage on this pin holds the device in reset. For normal operation, this pin is pulled up to 3.3-V supply with a 10kΩ pull-up resistor.
8.3.14 Trickle Charge and CS100
The WPC specification provides an End-of-Power Transfer message (EPT–01) to indicate charge complete.
Upon receipt of the charge complete message, the bq500414Q will change the LED indication. The exact
indication depends on the LED_MODE chosen.
In some battery charging applications there is a benefit to continue the charging process in trickle-charge mode
to top off the battery. There are several information packets in the WPC specification related to the levels of
battery charge (Charge Status). The bq500414Q uses these commands to enable top-off charging. The
bq500414Q changes the LED indication to reflect charge complete when a Charge Status message is 100%
received, but unlike the response to an EPT, it will not halt power transfer while the LED indicates charge
complete. The mobile device can use a CS100 packet to enable trickle charge mode.
If the reported charge status drops below 90%, normal charging indication will be resumed.
8.3.14.1 Over-Current Protection
The bq500414Q has an integrated current protection feature which monitors the input current reported by the
current sense resistor and amplifier. If the input current exceeds a predetermined threshold, a fault is indicated
and power transfer is halted for one minute.
If this feature is desired, the sense resistor and amplifier are required. If this feature is not desired, and WPC
v1.1 compliant (FOD) is not required, the I_SENSE input pin to the bq500414Q (pin 42) should be grounded.
NOTE
Always terminate the I_SENSE pin (pin 42), either with the output of a current monitor
circuit or by connecting to ground.
8.3.15 Over-Voltage Protection
When the Rx is quickly moved from a low coupling position to a high coupling position, the rectified voltage on
the Rx could get to very high before the Tx reacts to the change. Per WPC protocol, there is certain time duration
between the Control Error Packages, so the Tx will not be able to react instantaneously. The bq500414Q uses a
peak-detect circuit to prevent the Rx from being over-voltage.
16
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8.4 Device Functional Modes
8.4.1 Power Transfer
Power transfer depends on coil coupling. Coupling is dependant on the distance between coils, alignment, coil
dimensions, coil materials, number of turns, magnetic shielding, impedance matching, frequency, and duty cycle.
Most importantly, the receiver and transmitter coils must be aligned for best coupling and efficient power transfer.
The smaller the space between the coils is, the better the coupling; however, the practical distance is set to be
less than 5-mm, as defined within the WPC specification, to account for housing and interface surfaces.
Shielding is added as a backing to both the transmitter and receiver coils to direct the magnetic field to the
coupled zone. Magnetic fields outside the coupled zone do not transfer power. Thus, shielding also serves to
contain the fields to avoid coupling to other adjacent system components.
Regulation can be achieved by controlling any one of the coil coupling parameters. However, for WPC
compatibility, the transmitter-side coils and capacitance are specified and the resonant frequency point is fixed.
Power transfer is thus regulated by changing the frequency along the resonance curve from 120-kHz to 205-kHz,
(that is the higher the frequency is, the lower the power). Duty cycle remains constant at 50% throughout the
power band and is reduced only once 205-kHz is reached.
The WPC standard describes the dimensions, materials of the coils, and information regarding the tuning of the
coils to resonance. The value of the inductor and resonant capacitor are critical to proper operation and system
efficiency.
8.4.2 Communication
Communication within the WPC is from the receiver to the transmitter, where the receiver tells the transmitter to
send power and how much. In order to regulate, the receiver must communicate with the transmitter whether to
increase or decrease frequency. The receiver monitors the rectifier output and using Amplitude Modulation (AM),
sends packets of information to the transmitter. A packet is comprised of a preamble, a header, the actual
message and a checksum, as defined by the WPC standard.
The receiver sends a packet by modulating an impedance network. This AM signal reflects back as a change in
the voltage amplitude on the transmitter coil. The signal is demodulated and decoded by the transmitter-side
electronics and the frequency of its coil-drive output is adjusted to close the regulation loop. The bq500414Q
features internal digital demodulation circuitry.
The modulated impedance network on the receiver can either be resistive or capacitive. Figure 7 shows the
resistive modulation approach, where a resistor is periodically added to the load, and the resulting amplitude
change in the transmitter voltage. Figure 8 shows the capacitive modulation approach, where a capacitor is
periodically added to the load and the resulting amplitude change in the transmitter voltage.
Rectifier
Receiver Coil
Receiver
Capacitor
Amax
Modulation
Resitor
Operating state at logic “0”
A(0)
Operating state at logic “1”
A(1)
Comm
Fsw
a)
F, kHz
b)
Figure 7. Receiver Resistive Modulation Circuit
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Device Functional Modes (continued)
Rectifier
Receiver Coil
Receiver
Capacitor
Modulation
Capacitors
Amax
Comm
A(0)
Operating state at logic “ 0”
A(1)
Operating state at logic “ 1”
Fsw
F, kHz
Fo(1) < Fo(0)
a)
b)
Figure 8. Receiver Capacitive Modulation Circuit
8.4.3 Power Trains
The bq500414Q drives three independent half bridges. Each half bridge drives one coil from the coil set
assembly. The TPS28225 is the recommended driver device for this application. It features high-side drive
capability which enables the use of N-channel MOSFETs throughout. Gate-drive supply can be derived from a
primitive active voltage divider. A highly regulated supply is not required to drive MOSFET gates.
8.4.4 Signal Processing Components
The COMM signal used to control power transfer is derived from the coil voltage. Each coil has its own signal
processing chain. The AC coupled coil voltage is scaled down to a manageable level and biased to a 1-V offset.
Series connected diodes are provided for protection from any possible transients. The three signal processing
chains are then multiplexed together via analog switches. Thus, the correct signal processing chain and COMM
signal used to control power transfer is from the coil being driven.
18
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9 Applications and Implementation
9.1 Application Information
The bq500414Q device is a wireless power transmitter controller designed for automotive applications. It
integrates all functions required to control wireless power transfer to a WPC v1.1 compliant receiver. There are
several tools available for the design of the system. See the product folder on www.ti.com for more details. The
following sections highlight some of the system design considerations.
9.2 Typical Application
The application block diagram for the transmitter is shown in Figure 9.
6-16V
Input
ENABLE SEPIC
DETECT
PROXIMITY
SENSOR
TPS40210-Q1
SEPIC 12V
BC847CL
Simple 5V Linear
TPS54040-Q1
Buck 3.3V
I_SENSE
INA213-Q1
Current Shunt
Monitor
TPS28225-Q1
& DMG4800LSDQ
FETs
2
IC
bq500414Q
TPS28225-Q1
& DMG4800LSDQ
FETs
PWM
Tank/Coil
Assembly
Tank/Coil
Assembly
Tank/Coil
Assembly
TPS28225-Q1
& DMG4800LSDQ
FETs
FEEDBACK & SELECT
3x
SN74VLC1G3157Q1
Analog Mux
Figure 9. bq500414Q System Diagram
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Typical Application (continued)
9.2.1 Design Requirements
9.2.1.1 Capacitor Selection
Capacitor selection is critical to proper system operation. The total capacitance value of 2 x 68-nF ( 2 x (68-nF +
5.6-nF) in the center coil) is required in the resonant tank. This is the WPC system compatibility requirement, not
a guideline.
NOTE
A total capacitance value of 2 x 68-nF (additional 2 x 5.6-nF center coil) (C0G dielectric
type, 100V rating) is required in the resonant tank to achieve the correct resonance
frequency.
The capacitors chosen must be rated for at least 100 V and must be of a high quality C0G dielectric (sometimes
also called NP0). These are typically available in a 5% tolerance, which is adequate. The use of X7R types or
below is not recommended if WPC compliance is required because critical WPC Certification Testing, such as
the minimum modulation or ensured power requirements, might fail.
The designer can combine capacitors to achieve the desired capacitance value. Various combinations can work
depending on market availability. All capacitors must be of C0G types, not mixed with any other dielectric types.
9.2.1.2 Current Monitoring Requirements
The bq500414Q is WPC1.1 ready. In order to enable the PMOD or FOD features, current monitoring must be
provided in the design.
For proper scaling of the current monitor signal, the current sense resistor should be 40-mΩ and the current
shunt amplifier should have a gain of 50, such as the INA213Q1. For FOD accuracy, the current sense resistor
must be a quality component with 1% tolerance, at least 1/4-Watt rating, and a temperature stability of ±200
PPM. Proper current sensing techniques in the application hardware should also be observed.
9.2.1.3 All Unused Pins
All unused pins can be left open unless otherwise indicated. Please refer to the Pin Functions table. Grounding
of unused pins, if it is an option, can improve PCB layout.
9.2.1.4 Input Regulators
The bq500414Q requires 3.3-VDC to operate. A buck converter is used to step down from the automotive rail
voltage, such as the TPS54040 used in this design.
The power train bridge circuitry requires 12 V, and it is fed from a SEPIC converter using the TPS40210
controller. Since the automotive rail voltage can vary widely, this acts as a type of pre-regulator.
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Typical Application (continued)
9.2.1.5 Input Power Requirements
The design works with 6-V to 16-V input voltage. A6 Tx type requires 12-V system voltage. A SEPIC converter
TPS40210 is included in the design to work with 6-V to 16-V input voltage for automotive application.
9.2.2 Detailed Design Procedure
To begin the design process a few parameters must be decided upon. The design needs to know the following:
• Active or Passive Wake-up State
• EMI Shield
• LED Mode
• Number of Tx coils (1, 2, or 3)
9.2.2.1 Active or Passive Wake-up State
bq500414Q detects the pin 18 ~EN_PWR voltage at power up. If it's high, the bq500414Q will not send any
analog ping to detect the Rx, until SHUTDOWN command is disabled through I2C. A proximity sensor could be
used with this feature.
9.2.2.2 EMI Shield
EMI shield can help improve EMI performance. Pin 21 EMI_SHIELD is used to indicate if EMI shield is in use.
9.2.2.3 LED mode
bq500414Q can directly drive three LED outputs (pin 7 LED_A, pin 8 LED_B, and pin 9 LED_C). Select one of
the desired LED indication schemes by choosing the selection resistor connected between pin 44 LED_MODE
and GND.
9.2.2.4 Number of Transmitter Coils
bq500414Q supports 1, 2, or 3 coils. Please refer to the product folder on www.ti.com for more information on
the 3-coil design.
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Typical Application (continued)
9.2.3 Application Performance Plots
The system efficiency with A6 Tx type coil is shown in Figure 10. The SEPIC converter that provides 12-V
causes some efficiency drop.
80
80
No SEPIC Converter
70
70
60
60
50
Efficiency (%)
Efficiency (%)
No SEPIC Converter
With SEPIC Converter
40
30
20
50
With SEPIC Converter
40
30
20
Without SEPIC
10
0
0
1
2
3
Output Power (W)
4
Without SEPIC
10
With SEPIC
With SEPIC
0
5
0
C002
Figure 10. System Efficiency With A6 Tx Type Coil, With
and Without SEPIC Converter
1
2
3
Output Power (W)
4
5
C002
Figure 0. UNDEFINED
The frequency shift operation is shown in the Qi Sniffer capture in Figure 10. The Rx is placed on the Tx with no
load. The operating frequency is 154-kHz. Then a FREQ_SHIFT command is issued through I2C, to shift the
operating frequency to 190-kHz for 50,000-ms. After requested 50,000 ms, the operating frequency goes back to
its previous operating frequency, which is 154-kHz.
Figure 11. Qi Sniffer Capture of Frequency Shift Operation
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Typical Application (continued)
bq500414Q EVM is tested per CISPR25 EMI specification with and without the EMI shield. The measurement
results show > 24-dB improvement with the EMI shield at 5-W output power.
Peak Class 3 Limit
Peak Class 3 Limit
Peak Class 4 Limit
Peak Class 4 Limit
Figure 12. CISPR25 EMI Testing Result Without the EMI
Shield at 5-W Output Power
Figure 13. CISPR25 EMI Testing Result With the EMI
Shield at 5-W Output Power
10 Power Supply Recommendations
The device is designed to operate from an input voltage supply range between 3.0-V to 3.6-V, nominal 3.3-V.
The A6 Tx type requires 12-V system voltage. TPS40210 SEPIC converter is recommend to work with 6-V to 16V input.
11 Layout
11.1 Layout Guidelines
Careful PCB layout practice is critical to proper system operation. There are many references on proper PCB
layout techniques. A few good tips are as follows:
The Tx layout requires a 4-layer PCB layout for best ground plane technique. A 2-layer PCB layout can be
achieved though not as easily. Ideally, the approach to the layer stack-up has been:
• Layer 1 component placement and as much ground plane as possible
• Layer 2 clean ground
• Layer 3 finish routing
• Layer 4 clean ground
Thus, the circuitry is virtually sandwiched between grounds. This minimizes EMI noise emissions and also
provides a noise free voltage reference plane for device operation.
Keep as much copper as possible. Make sure the bq500414Q GND pins and the EPAD GND power pad have a
continuous flood connection to the ground plane. The power pad should also be stitched to the ground plane,
which also acts as a heat sink for the bq500414Q. A good GND reference is necessary for proper bq500414Q
operation, such as analog-digital conversion, clock stability and best overall EMI performance.
Separate the analog ground plane from the power ground plane and use only ONE tie point to connect grounds.
Having several tie points defeats the purpose of separating the grounds.
The COMM return signal from the resonant tank should be routed as a differential pair. This is intended to reduce
stray noise induction. The frequencies of concern warrant low-noise analog signaling techniques, such as
differential routing and shielding, but the COMM signal lines do not need to be impedance matched.
The DC-DC buck regulator used from the 12-V input supplies the bq500414Q with 3.3-V. Typically a single-chip
controller solution with integrated power FET and synchronous rectifier or outboard diode is used. Pull in the
buck inductor and power loop as close as possible to create a tight loop. Likewise, the power-train, full-bridge
components should be pulled together as tight as possible. See the bq500414Q EVM for an example of a good
layout technique.
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11.2 Layout Example
A DC-DC buck regulator is used to step down the system voltage to the 3.3-V supply to the bq500414Q. The
system voltage could be 12-V, or 6-V – 16-V depending on where the buck regulator input is. With such a stepdown ratio, switching duty-cycle will be low and the regulator will be mostly freewheeling. Therefore, place the
freewheeling diode current loop as close to the switching regulator as possible (loop in red). Place the buck
inductor and power loop as close to that as possible (loop in blue).
Buck Inductor
and
Power Loop
Diode Current
Loop
Figure 14. DC-DC Buck Regulator Layout
Make sure the bypass capacitors intended for the bq500414Q 3.3-V supply are actually bypassing these supply
pins (pin 33 V33D and pin 34 V33A) to solid ground plane. This means they need to be placed as close to the
device as possible and the traces must be as wide as possible.
Figure 15. Bypass Capacitors Layout
Make sure the bq500414Q has a continuous flood connection to the ground plane.
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Layout Example (continued)
Continuous GND
Figure 16. Continuous GND Layout
Proper current sensing layout technique is very important, as it directly affects the FOD and PMOD performance.
When sampling the very low voltages generated across a current sense resistor, be sure to use the so called,
"Four-wire" or "Kelvin-connection" technique. This is important to avoid introducing false voltage drops from
adjacent pads and copper power routes. It is common power supply layout technique.
In the below screen shot of a Texas Instruments PCB layout, the current sense resistor is R64. Notice the R18
and R15 sensing resisters are connected to the pads of R64 so there is no measurement error introduced by
copper conduction losses or copper resistance temperature dependency.
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www.ti.com
Layout Example (continued)
Figure 17. Current Sensing Layout
COMM+/COMM– sense lines should be run as a balanced or differential pair. The WPC packet information runs
at 2-kHz, which is essential audio frequency content and this balancing reduces noise pickup from the
surrounding switching power electronics. There is no need to tune or impedance-match these lines as would be
the case in RF signaling.
COMM+
COMM-
Figure 18. Balanced COMM Lines Layout
26
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Product Folder Links: bq500414Q
bq500414Q
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SLUSBE4B – JANUARY 2014 – REVISED JUNE 2014
12 Device and Documentation Support
12.1 Device Support
1. Technology, Wireless Power Consortium, http://www.wirelesspowerconsortium.com/
2. Analog Applications Journal, An Introduction to the Wireless Power Consortium Standard and TI’s Compliant
Solutions , Johns, Bill, (Texas Instruments Literature Number SLYT401)
3. Datasheet, Qi Compliant Wireless Power Transmitter Manager , (Texas Instruments Literature Number
SLUSAL8)
4. Datasheet, Integrated Wireless Power Supply Receiver, Qi (WPC) Compliant, bq51011, bq51013 , (Texas
Instruments Literature Number SLVSAT9)
5. Application Note, Building a Wireless Power Transmitter , (Texas Instruments Literature Number SLUA635)
6. Application Note, bqTESLA Transmitter Coil Vendors , (Texas Instruments Literature Number SLUA649)
12.2 Trademarks
All trademarks are the property of their respective owners.
12.3 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.
12.4 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.
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27
PACKAGE OPTION ADDENDUM
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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)
BQ500414QRGZRQ1
NRND
VQFN
RGZ
48
2500
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 110
BQ500414Q
BQ500414QRGZTQ1
NRND
VQFN
RGZ
48
250
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 110
BQ500414Q
(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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