TI INA219

INA219
www.ti.com........................................................................................................................................... SBOS448A – AUGUST 2008 – REVISED SEPTEMBER 2008
Zerø-Drift, Bi-Directional
CURRENT/POWER MONITOR with I2C™ Interface
FEATURES
DESCRIPTION
1
•
•
•
•
23
•
•
•
SENSES BUS VOLTAGES FROM 0V TO +26V
REPORTS CURRENT, VOLTAGE, AND POWER
16 PROGRAMMABLE ADDRESSES
HIGH ACCURACY: 1% (Max) OVER
TEMPERATURE
FILTERING OPTIONS
CALIBRATION REGISTERS
SOT23-8 AND SO-8 PACKAGES
The INA219 is a high-side current shunt and power
monitor with an I2C interface. The INA219 monitors
both shunt drop and supply voltage, with
programmable conversion times and filtering. A
programmable calibration value, combined with an
internal multiplier, enables direct readouts in
amperes. An additional multiplying register calculates
power in watts. The I2C interface features 16
programmable addresses.
The INA219 senses across shunts on buses that can
vary from 0V to 26V. The device uses a single +3V to
+5.5V supply, drawing a maximum of 1mA of supply
current. The INA219 operates from –40°C to +125°C.
APPLICATIONS
•
•
•
•
•
•
•
•
SERVERS
TELECOM EQUIPMENT
NOTEBOOK COMPUTERS
POWER MANAGEMENT
BATTERY CHARGERS
WELDING EQUIPMENT
POWER SUPPLIES
TEST EQUIPMENT
RELATED PRODUCTS
DESCRIPTION
DEVICE
Current/Power Monitor with Watchdog,
Peak-Hold, and Fast Comparator
Functions
INA209
Zerø-Drift, Low-Cost, Analog Current
Shunt Monitor Series in Small
Package
INA210-INA214
VS
(Supply Voltage)
VIN+ VIN-
INA219
´
Power Register
Data
2
Current Register
PGA
IC
Interface
CLK
A0
ADC
Voltage Register
A1
GND
1
2
3
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
I2C is a trademark of NXP Semiconductors.
All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2008, Texas Instruments Incorporated
INA219
SBOS448A – AUGUST 2008 – REVISED SEPTEMBER 2008........................................................................................................................................... www.ti.com
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
ORDERING INFORMATION (1)
PRODUCT
PACKAGE-LEAD
PACKAGE DESIGNATOR
PACKAGE MARKING
SO-8
D
I219A
SOT23-8
DCN
A219
INA219
(1)
For the most current package and ordering information see the Package Option Addendum at the end of this document, or see the TI
web site at www.ti.com.
ABSOLUTE MAXIMUM RATINGS (1)
Over operating free-air temperature range (unless otherwise noted).
Supply Voltage, VS
Analog Inputs,
VIN+, VIN–
Differential (VIN+) – (VIN–) (2)
UNIT
6
V
–26 to +26
V
-0.3 to +26
V
SDA
GND – 0.3 to +6
V
SCL
GND – 0.3 to VS + 0.3
V
Input Current Into Any Pin
5
mA
Open-Drain Digital Output Current
10
mA
Operating Temperature
–40 to +125
°C
Storage Temperature
–40 to +150
°C
Junction Temperature
ESD Ratings
(1)
(2)
2
Common-Mode
INA219
+150
°C
Human Body Model
4000
V
Charged-Device Model
750
V
Machine Model (MM)
200
V
Stresses above these ratings may cause permanent damage. Exposure to absolute maximum conditions for extended periods may
degrade device reliability. These are stress ratings only, and functional operation of the device at these or any other conditions beyond
those specified is not implied.
VIN+ and VIN– may have a differential voltage of –26V to +26V; however, the voltage at these pins must not exceed the range –0.3V to
+26V.
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INA219
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ELECTRICAL CHARACTERISTICS: VS = +3.3V
Boldface limits apply over the specified temperature range, TA = –25°C to +85°C.
At TA = +25°C, VIN+ = 12V, VSENSE = (VIN+ – VIN–) = 32mV, PGA = ÷ 1, and BRNG (1) = 1, unless otherwise noted.
INA219
PARAMETER
TEST CONDITIONS
MIN
PGA = ÷ 1
0
PGA = ÷ 2
PGA = ÷ 4
TYP
MAX
UNIT
±40
mV
0
±80
mV
0
±160
mV
PGA = ÷ 8
0
±320
mV
BRNG = 1
0
32
V
BRNG = 0
0
16
VIN+ = 0V to 26V
100
INPUT
Full-Scale Current Sense (Input) Voltage Range
Bus Voltage (Input Voltage) Range (2)
Common-Mode Rejection
Offset Voltage, RTI (3)
CMRR
VOS
PSRR
±10
±100
µV
PGA = ÷ 2
±20
±125
µV
PGA = ÷ 4
±30
±150
µV
PGA = ÷ 8
±40
±200
VS = 3V to 5.5V
Current Sense Gain Error
vs Temperature
Input Impedance
V
dB
PGA = ÷ 1
vs Temperature
vs Power Supply
120
µV
0.1
µV/°C
10
µV/V
±40
m%
10
ppm/°C
Active Mode
VIN+ Pin
20
µA
VIN– Pin
20 || 320
µA || kΩ
Input Leakage (4)
Power-Down Mode
VIN+ Pin
0.1
±0.5
µA
VIN– Pin
0.1
±0.5
µA
DC ACCURACY
ADC Basic Resolution
12
Bits
1 LSB Step Size
Shunt Voltage
10
µV
Bus Voltage
4
mV
Current Measurement Error
±0.2
over Temperature
Bus Voltage Measurement Error
±0.2
over Temperature
±0.5
%
±1
%
±0.5
%
±1
Differential Nonlinearity
±0.1
%
LSB
ADC TIMING
ADC Conversion Time
12-Bit
532
586
µs
11-Bit
276
304
µs
10-Bit
148
163
µs
9-Bit
84
93
µs
Minimum Convert Input Low Time
(1)
(2)
(3)
(4)
µs
4
BRNG is bit 13 of the Configuration Register.
This parameter only expresses the full-scale range of the ADC scaling. In no event should more than 26V be applied to this device.
Referred-to-input (RTI).
Input leakage is positive (current flowing into the pin) for the conditions shown at the top of the table. Negative leakage currents can
occur under different input conditions.
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INA219
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ELECTRICAL CHARACTERISTICS: VS = +3.3V (continued)
Boldface limits apply over the specified temperature range, TA = –25°C to +85°C.
At TA = +25°C, VIN+ = 12V, VSENSE = (VIN+ – VIN–) = 32mV, PGA = ÷ 1, and BRNG = 1, unless otherwise noted.
INA219
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
28
35
ms
1
µA
V
SMBus
SMBus Timeout (5)
DIGITAL INPUTS
(SDA as Input, SCL, A0, A1)
Input Capacitance
3
0 ≤ VIN ≤ VS
Leakage Input Current
0.1
pF
Input Logic Levels:
VIH
0.7 (VS)
6
VIL
–0.3
0.3 (VS)
Hysteresis
500
V
mV
OPEN-DRAIN DIGITAL OUTPUTS (SDA)
Logic '0' Output Level
High-Level Output Leakage Current
ISINK = 3mA
0.15
0.4
V
VOUT = VS
0.1
1
µA
POWER SUPPLY
Operating Supply Range
+3
+5.5
V
0.7
1
mA
Quiescent Current, Power-Down Mode
6
15
µA
Power-On Reset Threshold
2
Quiescent Current
V
TEMPERATURE RANGE
Specified Temperature Range
–25
+85
°C
Operating Temperature Range
–40
+125
°C
Thermal Resistance (6)
(5)
(6)
4
θJA
SOT23-8
142
°C/W
SO-8
120
°C/W
SMBus timeout in the INA219 resets the interface any time SCL or SDA is low for over 28ms.
θJA value is based on JEDEC low-K board.
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INA219
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PIN CONFIGURATIONS
DCN PACKAGE
SOT23-8
(Top View)
D PACKAGE
SO-8
(Top View)
VIN+
1
8
A1
VIN-
2
7
A0
GND
3
6
SDA
VS
4
5
SCL
A1
1
8
VIN+
A0
2
7
VIN-
SDA
3
6
GND
SCL
4
5
VS
PIN DESCRIPTIONS: SOT23-8
SOT23-8
(DCN)
PIN NO
NAME
1
VIN+
Positive differential shunt voltage. Connect to positive side of shunt resistor.
DESCRIPTION
2
VIN–
Negative differential shunt voltage. Connect to negative side of shunt resistor. Bus voltage is measured
from this pin to ground.
3
GND
Ground.
4
VS
Power supply, 3V to 5.5V.
5
SCL
Serial bus clock line.
6
SDA
Serial bus data line.
7
A0
Address pin. Table 1 shows pin settings and corresponding addresses.
8
A1
Address pin. Table 1 shows pin settings and corresponding addresses.
PIN DESCRIPTIONS: SO-8
SO-8
(D)
PIN NO
NAME
DESCRIPTION
1
A1
Address pin. Table 1 shows pin settings and corresponding addresses.
2
A0
Address pin. Table 1 shows pin settings and corresponding addresses.
3
SDA
Serial bus data line.
4
SCL
Serial bus clock line.
5
VS
6
GND
Power supply, 3V to 5.5V.
Ground.
7
VIN–
Negative differential shunt voltage. Connect to negative side of shunt resistor. Bus voltage is measured
from this pin to ground.
8
VIN+
Positive differential shunt voltage. Connect to positive side of shunt resistor.
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INA219
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TYPICAL CHARACTERISTICS
At TA = +25°C, VIN+ = 12V, VSENSE = (VIN+ – VIN–) = 32mV, PGA = ÷ 1, and BRNG = 1, unless otherwise noted.
ADC SHUNT OFFSET vs TEMPERATURE
100
-10
80
-20
60
-30
40
Offset (mV)
Gain (dB)
FREQUENCY RESPONSE
0
-40
-50
-60
20
0
-20
-70
-40
-80
-60
-90
-80
-100
-100
100
10
1k
10k
100k
320mV Range
160mV Range
1M
80mV Range
-40 -25
0
Input Frequency (Hz)
40mV Range
25
Figure 1.
80
45
60
40
40
35
160mV Range
0
-20
-40
125
30
25
20
16V Range
32V Range
15
80mV Range 40mV Range
-60
10
-80
5
0
-100
-40 -25
0
25
50
75
100
-40 -25
125
0
25
50
75
100
125
Temperature (°C)
Temperature (°C)
Figure 3.
Figure 4.
ADC BUS GAIN ERROR vs TEMPERATURE
INTEGRAL NONLINEARITY vs INPUT VOLTAGE
100
20
80
15
60
10
40
16V
20
INL (mV)
Gain Error (m%)
100
ADC BUS VOLTAGE OFFSET vs TEMPERATURE
50
Offset (mV)
Gain Error (m%)
ADC SHUNT GAIN ERROR vs TEMPERATURE
320mV Range
75
Figure 2.
100
20
50
Temperature (°C)
0
-20
0
-5
32V
-40
5
-10
-60
-15
-80
-100
-40 -25
0
25
50
75
100
125
-20
-0.4
Figure 5.
6
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
Input Voltage (V)
Temperature (°C)
Figure 6.
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TYPICAL CHARACTERISTICS (continued)
At TA = +25°C, VIN+ = 12V, VSENSE = (VIN+ – VIN–) = 32mV, PGA = ÷ 1, and BRNG = 1, unless otherwise noted.
INPUT CURRENTS WITH LARGE DIFFERENTIAL
VOLTAGES
(VIN+ at 12V, Sweep of VIN–)
2.0
ACTIVE IQ vs TEMPERATURE
1.2
VS+ = 5V
1.0
1.0
VS = 5V
0.8
0.5
IQ (mA)
Input Currents (mA)
1.5
VS+ = 3V
0
VS+ = 3V
0.6
VS = 3V
0.4
-0.5
0.2
-1.0
VS+ = 5V
0
-1.5
0
10
5
15
20
25
30
25
50
Temperature (°C)
Figure 7.
Figure 8.
75
100
125
ACTIVE IQ vs I2C CLOCK FREQUENCY
SHUTDOWN IQ vs TEMPERATURE
16
1.0
14
0.9
VS = 5V
0.8
12
0.7
IQ (mA)
10
IQ (mA)
0
-40 -25
VIN- Voltage (V)
VS = 5V
8
6
VS = 3V
4
0.6
VS = 3V
0.5
0.4
0.3
0.2
2
0.1
0
0
-40 -25
0
25
50
75
100
125
100k
10k
1k
Temperature (°C)
SCL Frequency (Hz)
Figure 9.
Figure 10.
1M
10M
SHUTDOWN IQ vs I2C CLOCK FREQUENCY
300
250
VS = 5V
IQ (mA)
200
150
100
50
VS = 3V
0
1k
10k
100k
1M
10M
SCL Frequency (Hz)
Figure 11.
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INA219
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REGISTER BLOCK DIAGRAM
Power
(1)
Bus Voltage
(1)
´
Current
Shunt Voltage
Channel
(1)
ADC
Bus Voltage
Channel
Full-Scale Calibration
(2)
´
Shunt Voltage
(1)
PGA
(In Configuration Register)
NOTES:
(1) Read-only
(2) Read/write
Data Registers
Figure 12. INA219 Register Block Diagram
8
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APPLICATION INFORMATION
The INA219 is a digital current-shunt monitor with an
I2C and SMBus-compatible interface. It provides
digital current, voltage, and power readings
necessary
for
accurate
decision-making
in
precisely-controlled systems. Programmable registers
allow flexible configuration for measurement
resolution,
and
continuousversus-triggered
operation.
Detailed
register
information appears at the end of this data sheet,
beginning with Table 2. See the Register Block
Diagram for a block diagram of the INA219.
INA219 TYPICAL APPLICATION
Figure 13 shows a typical application circuit for the
INA219. Use a 0.1µF ceramic capacitor for
power-supply bypassing, placed as closely as
possible to the supply and ground pins.
The input filter circuit consisting of RF1, RF2, and CF is
not necessary in most applications. If the need for
filtering is unknown, reserve board space for the
components and install 0Ω resistors unless a filter is
needed. See the Filtering and Input Considerations
section.
The pull-up resistors shown on the SDA and SCL
lines are not needed if there are pull-up resistors on
these same lines elsewhere in the system. Resistor
values shown are typical: consult either the I2C or
SMBus specification to determine the acceptable
minimum or maximum values.
BUS OVERVIEW
The I2C interface is used throughout this data sheet
as the primary example, with SMBus protocol
specified only when a difference between the two
systems is being addressed. Two bidirectional lines,
SCL and SDA, connect the INA219 to the bus. Both
SCL and SDA are open-drain connections.
The device that initiates the transfer is called a
master, and the devices controlled by the master are
slaves. The bus must be controlled by a master
device that generates the serial clock (SCL), controls
the bus access, and generates START and STOP
conditions.
To address a specific device, the master initiates a
START condition by pulling the data signal line (SDA)
from a HIGH to a LOW logic level while SCL is HIGH.
All slaves on the bus shift in the slave address byte
on the rising edge of SCL, with the last bit indicating
whether a read or write operation is intended. During
the ninth clock pulse, the slave being addressed
responds to the master by generating an
Acknowledge and pulling SDA LOW.
Data transfer is then initiated and eight bits of data
are sent, followed by an Acknowledge bit. During
data transfer, SDA must remain stable while SCL is
HIGH. Any change in SDA while SCL is HIGH is
interpreted as a START or STOP condition.
Once all data have been transferred, the master
generates a STOP condition, indicated by pulling
SDA from LOW to HIGH while SCL is HIGH. The
INA219 includes a 28ms timeout on its interface to
prevent locking up an SMBus.
The INA219 offers compatibility with both I2C and
SMBus interfaces. The I2C and SMBus protocols are
essentially compatible with one another.
Current
Shunt
Power Bus
(0V to 26V)
Supply Voltage
(INA219 Power Supply Range is
3V to 5.5V)
Load
RF1
RF2
CBYPASS
0.1mF
(typical)
CF
VIN+
RPULLUP
3.3kW
(typical)
VIN-
INA219
´
SDA
Power Register
SCL
2
Current Register
PGA
IC
Interface
ADC
RPULLUP
3.3kW
(typical)
Data (SDA)
Clock (SCL)
A0
A1
Voltage Register
GND
Figure 13. Typical Application Circuit
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Serial Bus Address
WRITING TO/READING FROM THE INA219
To communicate with the INA219, the master must
first address slave devices via a slave address byte.
The slave address byte consists of seven address
bits, and a direction bit indicating the intent of
executing a read or write operation.
Accessing a particular register on the INA219 is
accomplished by writing the appropriate value to the
register pointer. Refer to Table 2 for a complete list of
registers and corresponding addresses. The value for
the register pointer as shown in Figure 17 is the first
byte transferred after the slave address byte with the
R/W bit LOW. Every write operation to the INA219
requires a value for the register pointer.
The INA219 has two address pins, A0 and A1.
Table 1 describes the pin logic levels for each of the
16 possible addresses. The state of pins A0 and A1
is sampled on every bus communication and should
be set before any activity on the interface occurs. The
address pins are read at the start of each
communication event.
Table 1. INA219 Address Pins and
Slave Addresses
A1
A0
SLAVE ADDRESS
GND
GND
1000000
GND
VS+
1000001
GND
SDA
1000010
GND
SCL
1000011
VS+
GND
1000100
VS+
VS+
1000101
VS+
SDA
1000110
VS+
SCL
1000111
SDA
GND
1001000
SDA
VS+
1001001
SDA
SDA
1001010
SDA
SCL
1001011
SCL
GND
1001100
SCL
VS+
1001101
SCL
SDA
1001110
SCL
SCL
1001111
Serial Interface
The INA219 operates only as a slave device on the
I2C bus and SMBus. Connections to the bus are
made via the open-drain I/O lines SDA and SCL. The
SDA and SCL pins feature integrated spike
suppression filters and Schmitt triggers to minimize
the effects of input spikes and bus noise. The INA219
supports the transmission protocol for fast (1kHz to
400kHz) and high-speed (1kHz to 3.4MHz) modes.
All data bytes are transmitted most significant byte
first.
10
Writing to a register begins with the first byte
transmitted by the master. This byte is the slave
address, with the R/W bit LOW. The INA219 then
acknowledges receipt of a valid address. The next
byte transmitted by the master is the address of the
register to which data will be written. This register
address value updates the register pointer to the
desired register. The next two bytes are written to the
register addressed by the register pointer. The
INA219 acknowledges receipt of each data byte. The
master may terminate data transfer by generating a
START or STOP condition.
When reading from the INA219, the last value stored
in the register pointer by a write operation determines
which register is read during a read operation. To
change the register pointer for a read operation, a
new value must be written to the register pointer. This
write is accomplished by issuing a slave address byte
with the R/W bit LOW, followed by the register pointer
byte. No additional data are required. The master
then generates a START condition and sends the
slave address byte with the R/W bit HIGH to initiate
the read command. The next byte is transmitted by
the slave and is the most significant byte of the
register indicated by the register pointer. This byte is
followed by an Acknowledge from the master; then
the slave transmits the least significant byte. The
master acknowledges receipt of the data byte. The
master may terminate data transfer by generating a
Not-Acknowledge after receiving any data byte, or
generating a START or STOP condition. If repeated
reads from the same register are desired, it is not
necessary to continually send the register pointer
bytes; the INA219 retains the register pointer value
until it is changed by the next write operation.
Figure 14 and Figure 15 show read and write
operation timing diagrams, respectively. Note that
register bytes are sent most-significant byte first,
followed by the least significant byte. Figure 16
shows the timing diagram for the SMBus Alert
response operation. Figure 17 illustrates a typical
register pointer configuration.
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Start By
Master
1
1
1
1
0
0
A3
A2
A1
A0
(1)
R/W
Frame 1 Two-Wire Slave Address Byte
0
A3
A2
A1
A0
(1)
9
ACK By
INA219
R/W
1
P7
P6
9
ACK By
INA219
1
D15 D14
P4
P3
P2
D13
P1
Frame 2 Register Pointer Byte
P5
D12
D11 D10
D9
(2)
From
INA219
Frame 2 Data MSByte
9
ACK By
INA219
P0
1
D15 D14
D13
D8
9
1
D6
9
ACK By
INA219
D8
D7
ACK By
Master
D9
Frame 3 Data MSByte
D12 D11 D10
NOTES: (1) The value of the Slave Address Byte is determined by the settings of the A0 and A1 pins.
Refer to Table 1.
(2) Read data is from the last register pointer location. If a new register is desired, the register
pointer must be updated. See Figure 19.
(3) ACK by Master can also be sent.
0
Frame 1 Two-Wire Slave Address Byte
D5
1
D7
D4
D3
From
INA219
D5
D4
D2
D3
D1
(2)
D2
Frame 3 Data LSByte
D6
9
9
ACK By
INA219
D0
NoACK By
Master
D0
D1
Frame 4 Data LSByte
(3)
Stop
Stop By
Master
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SCL
SDA
SCL
SDA
Start By
Master
NOTE (1): The value of the Slave Address Byte is determined by the settings of the A0 and A1 pins. Refer to Table 1.
Figure 15. Timing Diagram for Read Word Format
Figure 14. Timing Diagram for Write Word Format
INA219
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ALERT
1
9
1
9
SCL
SDA
0
0
0
1
1
0
0
1
R/W
Start By
Master
0
0
A3
A2
ACK By
INA219
A1
A0
0
From
INA219
Frame 1 SMBus ALERT Response Address Byte
Frame 2 Slave Address Byte
NACK By
Master
Stop By
Master
(1)
NOTE (1): The value of the Slave Address Byte is determined by the settings of the A0 and A1 pins. Refer to Table 1.
Figure 16. Timing Diagram for SMBus ALERT
1
9
1
9
SCL
¼
SDA
1
0
0
A3
A2
A1
A0
R/W
Start By
Master
P7
P6
P5
P4
P3
P2
P1
ACK By
INA219
Frame 1 Two-Wire Slave Address Byte
(1)
P0
Stop
ACK By
INA219
Frame 2 Register Pointer Byte
NOTE (1): The value of the Slave Address Byte is determined by the settings of the A0 and A1 pins. Refer to Table 1.
Figure 17. Typical Register Pointer Set
12
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High-Speed I2C Mode
The master then generates a repeated start condition
(a repeated start condition has the same timing as
the start condition). After this repeated start condition,
the protocol is the same as F/S mode, except that
transmission speeds up to 3.4Mbps are allowed.
Instead of using a stop condition, repeated start
conditions should be used to secure the bus in
HS-mode. A stop condition ends the HS-mode and
switches all the internal filters of the INA219 to
support the F/S mode.
When the bus is idle, both the SDA and SCL lines are
pulled high by the pull-up devices. The master
generates a start condition followed by a valid serial
byte containing High-Speed (HS) master code
00001XXX. This transmission is made in fast
(400kbps) or standard (100kbps) (F/S) mode at no
more than 400kbps. The INA219 does not
acknowledge the HS master code, but does
recognize it and switches its internal filters to support
3.4Mbps operation.
t(LOW)
tF
tR
t(HDSTA)
SCL
t(HDSTA)
t(HIGH)
t(SUSTO)
t(SUSTA)
t(HDDAT)
t(SUDAT)
SDA
t(BUF)
P
S
S
P
Figure 18. Bus Timing Diagram
Bus Timing Diagram Definitions
FAST MODE
PARAMETER
HIGH-SPEED MODE
MIN
MAX
MIN
MAX
UNITS
SCL Operating Frequency
f(SCL)
0.001
0.4
0.001
3.4
MHz
Bus Free Time Between STOP and START
Condition
t(BUF)
600
160
ns
Hold time after repeated START condition.
After this period, the first clock is generated.
t(HDSTA)
100
100
ns
Repeated START Condition Setup Time
t(SUSTA)
100
100
ns
STOP Condition Setup Time
t(SUSTO)
100
100
ns
Data Hold Time
t(HDDAT)
0
0
ns
Data Setup Time
t(SUDAT)
100
10
ns
SCL Clock LOW Period
t(LOW)
1300
160
ns
SCL Clock HIGH Period
t(HIGH)
600
Clock/Data Fall Time
tF
300
160
ns
Clock/Data Rise Time
tR
300
160
ns
Clock/Data Rise Time for SCLK ≤ 100kHz
tR
1000
60
ns
ns
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Power-Up Conditions
All current and power calculations are performed in
the background and do not contribute to conversion
time; conversion times shown in the Electrical
Characteristics table can be used to determine the
actual conversion time.
Power-up conditions apply to a software reset via the
RST bit (bit 15) in the Configuration Register, or the
I2C bus General Call Reset.
BASIC ADC FUNCTIONS
Power-Down mode reduces the quiescent current
and turns off current into the INA219 inputs, avoiding
any supply drain. Full recovery from Power-Down
requires 40µs. ADC Off mode (set by the
Configuration Register, MODE bits) stops all
conversions.
The two analog inputs to the INA219, VIN+ and VIN–,
connect to a shunt resistor in the bus of interest. The
INA219 is typically powered by a separate supply
from +3V to +5.5V. The bus being sensed can vary
from 0V to 26V. There are no special considerations
for power-supply sequencing (for example, a bus
voltage can be present with the supply voltage off,
and vice-versa). The INA219 senses the small drop
across the shunt for shunt voltage, and senses the
voltage with respect to ground from VIN– for the bus
voltage. Figure 19 illustrates this operation.
In triggered mode, the external Convert line becomes
active. Convert commands are initiated by taking the
Convert line low for a minimum of 4µs. The Convert
line may be connected high when unused. Any
re-trigger of the Convert line during a conversion is
ignored, and the Convert line state is disregarded
until the conversion ends. There are several available
triggered modes; however, all conversions are
performed repeatedly up to the number set in the
Averaging function (Configuration Register, BADC
and SADC bits).
When the INA219 is in the normal operating mode
(that is, MODE bits of the Configuration Register are
set to '111'), it continuously converts the shunt
voltage up to the number set in the shunt voltage
averaging function (Configuration Register, SADC
bits). The device then converts the bus voltage up to
the number set in the bus voltage averaging
(Configuration Register, BADC bits). The Mode
control in the Configuration Register also permits
selecting modes to convert only voltage or current,
either continuously or in response to an event
(triggered).
If the Convert line is held low, writing any of the
triggered convert modes into the Configuration
Register (even if the desired mode is already
programmed into the register) triggers a single-shot
conversion.
VSHUNT = VIN+ - VINTypically < 50mV
+
-
Current
Shunt
Supply
Load
INA219 Power-Supply Voltage
3V to 5.5V
3.3V Supply
VIN+
VS
VIN-
INA219
´
Power Register
Data (SDA)
Clock (SCL)
2
VBUS = VIN- - GND
Current Register
Range of 0V to 26V
Typical Application 12V
PGA
IC
Interface
A0
ADC
Voltage Register
A1
GND
Figure 19. INA219 Configured for Shunt and Bus Voltage Measurement
14
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Although the INA219 can be read at any time, and
the data from the last conversion remain available,
the Conversion Ready bit (Status Register, CNVR bit)
is provided to help co-ordinate one-shot or triggered
conversions. The Conversion Ready bit is set after all
conversions, averaging, and multiplication operations
are complete.
The Conversion Ready bit clears under these
conditions:
1. Writing to the Configuration Register, except
when configuring the MODE bits for Power Down
or ADC off (Disable) modes;
2. Reading the Status Register; or
3. Triggering a single-shot conversion with the
Convert pin.
Power Measurement
Current and bus voltage are converted at different
points in time, depending on the resolution and
averaging mode settings. For instance, when
configured for 12-bit and 128 sample averaging, up to
68ms in time between sampling these two values is
possible. Again, these calculations are performed in
the background and do not add to the overall
conversion time.
PGA Function
If larger full-scale shunt voltages are desired, the
INA219 provides a PGA function that increases the
full-scale range up to 2, 4, or 8 times (320mV).
Additionally, the bus voltage measurement has two
full-scale ranges: 16V or 32V.
Compatibility with TI Hot Swap Controllers
The INA219 is designed for compatibility with hot
swap controllers such the TI TPS2490. The TPS2490
uses a high-side shunt with a limit at 50mV; the
INA219 full-scale range of 40mV enables the use of
the same shunt for current sensing below this limit.
When sensing is required at (or through) the 50mV
sense point of the TPS2490, the PGA of the INA219
can be set to ÷2 to provide an 80mV full-scale range.
Filtering and Input Considerations
Measuring current is often noisy, and such noise can
be difficult to define. The INA219 offers several
options for filtering by choosing resolution and
averaging in the Configuration Register. These
filtering options can be set independently for either
voltage or current measurement.
The internal ADC is based on a delta-sigma (ΔΣ)
front-end with a 500kHz (±30%) typical sampling rate.
This architecture has good inherent noise rejection;
however, transients that occur at or very close to the
sampling rate harmonics can cause problems.
Because these signals are at 1MHz and higher, they
can be dealt with by incorporating filtering at the input
of the INA219. The high frequency enables the use of
low-value series resistors on the filter for negligible
effects on measurement accuracy. In general, filtering
the INA219 input is only necessary if there are
transients at exact harmonics of the 500kHz (±30%)
sampling rate (>1MHz). Filter using the lowest
possible series resistance and ceramic capacitor.
Recommended values are 0.1µF to 1.0µF. Figure 20
shows the INA219 with an additonal filter added at
the input.
Current
Shunt
Load
Supply
RFILTER 10W
RFILTER 10W
Supply Voltage
3.3V Supply
0.1mF to 1mF
Ceramic Capacitor
VIN+ VIN-
VS
INA219
´
Power Register
Data (SDA)
Clock (SCL)
2
Current Register
PGA
IC
Interface
A0
ADC
Voltage Register
A1
GND
Figure 20. INA219 with Input Filtering
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Overload conditions are another consideration for the
INA219 inputs. The INA219 inputs are specified to
tolerate 26V across the inputs. A large differential
scenario might be a short to ground on the load side
of the shunt. This type of event can result in full
power-supply voltage across the shunt (as long the
power supply or energy storage capacitors support it).
It must be remembered that removing a short to
ground can result in inductive kickbacks that could
exceed the 26V differential and common-mode rating
of the INA219. Inductive kickback voltages are best
dealt with by zener-type transient-absorbing devices
(commonly called transzorbs) combined with
sufficient energy storage capacitance.
In applications that do not have large energy storage
electrolytics on one or both sides of the shunt, an
input overstress condition may result from an
excessive dV/dt of the voltage applied to the input. A
hard physical short is the most likely cause of this
event, particularly in applications with no large
electrolytics present. This problem occurs because an
excessive dV/dt can activate the ESD protection in
the INA219 in systems where large currents are
available. Testing has demonstrated that the addition
of 10Ω resistors in series with each input of the
INA219 sufficiently protects the inputs against dV/dt
failure up to the 26V rating of the INA219. These
resistors have no significant effect on accuracy.
16
Simple Current Shunt Monitor Usage
(No Programming Necessary)
The INA219 can be used without any programming if
it is only necessary to read a shunt voltage drop and
bus voltage with the default 12-bit resolution, 320mV
shunt full-scale range (PGA=÷8), 32V bus full-scale
range, and continuous conversion of shunt and bus
voltage.
Without programming, current is measured by
reading the shunt voltage. The Current Register and
Power Register are only available if the Calibration
Register contains a programmed value.
Programming the INA219
The default power-up states of the registers are
shown in the INA219 register descriptions section of
this data sheet. These registers are volatile, and if
programmed to other than default values, must be
re-programmed at every device power-up. Detailed
information on programming the Calibration Register
specifically is given in the section, Programming the
INA219 Power Measurement Engine.
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PROGRAMMING THE INA219 POWER MEASUREMENT ENGINE
Calibration Register and Scaling
The Calibration Register makes it possible to set the scaling of the Current and Power Registers to whatever
values are most useful for a given application. One strategy may be to set the Calibration Register such that the
largest possible number is generated in the Current Register or Power Register at the expected full-scale point;
this approach yields the highest resolution. The Calibration Register can also be selected to provide values in the
Current and Power Registers that either provide direct decimal equivalents of the values being measured, or
yield a round LSB number. After these choices have been made, the Calibration Register also offers possibilities
for end user system-level calibration, where the value is adjusted slightly to cancel total system error.
Below are two examples for configuring the INA219 calibration. Both examples are written so the information
directly relates to the calibration setup found in the INA219EVM software.
Calibration Example 1: Calibrating the INA219 with no possibility for overflow. (Note that the numbers
used in this example are the same used with the INA219EVM software as shown in Figure 21.)
1. Establish the following parameters:
VBUS_MAX = 32
VSHUNT_MAX = 0.32
RSHUNT = 0.5
2. Using Equation 1, determine the maximum possible current .
VSHUNT_MAX
MaxPossible_I =
RSHUNT
MaxPossible_I = 0.64
(1)
3. Choose the desired maximum current value. This value is selected based on system expectations.
Max_Expected_I = 0.6
4. Calculate the possible range of current LSBs. To calculate this range, first compute a range of LSBs that is
appropriate for the design. Next, select an LSB within this range. Note that the results will have the most
resolution when the minimum LSB is selected. Typically, an LSB is selected to be the nearest round number
to the minimum LSB value.
Max_Expected_I
Minimum_LSB =
32767
Minimum_LSB = 18.311 ´ 10-6
(2)
Max_Expected_I
4096
Maximum_LSB = 146.520 ´ 10-6
Maximum_LSB =
(3)
Choose an LSB in the range: Minimum_LSB<Selected_LSB < Maximum_LSB
Current_LSB = 20 × 10–6
Note:
This value was selected to be a round number near the Minimum_LSB. This selection allows for
good resolution with a rounded LSB.
5. Compute the Calibration Register value using Equation 4:
0.04096
Cal = trunc Current_LSB ´ R
SHUNT
Cal = 4096
(4)
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6. Calculate the Power LSB, using Equation 5. Equation 5 shows a general formula; because the bus voltage
measurement LSB is always 4mV, the power formula reduces to the calculated result.
Power_LSB = 20 Current_LSB
Power_LSB = 400 ´ 10-6
(5)
7. Compute the maximum current and shunt voltage values (before overflow), as shown by Equation 6 and
Equation 7. Note that both Equation 6 and Equation 7 involve an If - then condition:
Max_Current = Current_LSB ´ 32767
Max_Current = 0.65534
(6)
If Max_Current ≥ Max Possible_I then
Max_Current_Before_Overflow = MaxPossible_I
Else
Max_Current_Before_Overflow = Max_Current
End If
(Note that Max_Current is greater than MaxPossible_I in this example.)
Max_Current_Before_Overflow = 0.64 (Note: This result is displayed by software as seen in Figure 21.)
Max_ShuntVoltage = Max_Current_Before_Overflow ´ RSHUNT
Max_ShuntVoltage = 0.32
(7)
If Max_ShuntVoltage ≥ VSHUNT_MAX
Max_ShuntVoltage_Before_Overflow = VSHUNT_MAX
Else
Max_ShuntVoltage_Before_Overflow= Max_ShuntVoltage
End If
(Note that Max_ShuntVoltage is greater than VSHUNT_MAX in this example.)
Max_ShuntVoltage_Before_Overflow = 0.32 (Note: This result is displayed by software as seen in
Figure 21.)
8. Compute the maximum power with Equation 8.
MaximumPower = Max_Current_Before_Overflow ´ VBUS_MAX
MaximumPower = 20.48
(8)
9. (Optional second Calibration step.) Compute corrected full-scale calibration value based on measured
current.
INA219_Current = 0.63484
MeaShuntCurrent = 0.55
Corrected_Full_Scale_Cal = trunc
Cal ´ MeasShuntCurrent
INA219_Current
Corrected_Full_Scale_Cal = 3548
(9)
Figure 21 illustrates how to perform the same procedure discussed in this example using the automated
INA219EVM software. Note that the same numbers used in the nine-step example are used in the software
example in Figure 21. Also note that Figure 21 illustrates which results correspond to which step (for example,
the information entered in Step 1 is enclosed in a box in Figure 21 and labeled).
18
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Figure 21. INA219 Calibration Sofware Automatically Computes Calibration Steps 1-9
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Calibration Example 2 (Overflow Possible)
This design example uses the nine-step procedure for calibrating the INA219 where overflow is possible.
Figure 22 illustrates how the same procedure is performed using the automated INA219EVM software. Note that
the same numbers used in the nine-step example are used in the software example in Figure 22. Also note that
Figure 22 illustrates which results correspond to which step (for example, the information entered in Step 1 is
circled in Figure 22 and labeled).
1. Establish the following parameters:
VBUS_MAX = 32
VSHUNT_MAX = 0.32
RSHUNT = 5
2. Determine the maximum possible current using Equation 10:
VSHUNT_MAX
MaxPossible_I =
RSHUNT
MaxPossible_I = 0.064
(10)
3. Choose the desired maximum current value: Max_Expected_I, ≤ MaxPossible_I. This value is selected
based on system expectations.
Max_Expected_I = 0.06
4. Calculate the possible range of current LSBs. This calculation is done by first computing a range of LSB's
that is appropriate for the design. Next, select an LSB withing this range. Note that the results will have the
most resolution when the minimum LSB is selected. Typically, an LSB is selected to be the nearest round
number to the minimum LSB.
Max_Expected_I
Minimum_LSB =
32767
Minimum_LSB = 1.831 ´ 10-6
(11)
Max_Expected_I
4096
Maximum_LSB = 14.652 ´ 10-6
Maximum_LSB =
(12)
Choose an LSB in the range: Minimum_LSB<Selected_LSB<Maximum_LSB
Current_LSB = 1.9 × 10–6
Note:
This value was selected to be a round number near the Minimum_LSB. This section allows for good
resolution with a rounded LSB.
5. Compute the calibration register using Equation 13:
Cal = trunc
0.04096
Current_LSB ´ RSHUNT
Cal = 4311
(13)
6. Calculate the Power LSB using Equation 14. Equation 14 shows a general formula; because the bus voltage
measurement LSB is always 4mV, the power formula reduces to calculate the result.
Power_LSB = 20 Current_LSB
Power_LSB = 38 ´ 10-6
20
(14)
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7. Compute the maximum current and shunt voltage values (before overflow), as shown by Equation 15 and
Equation 16. Note that both Equation 15 and Equation 16 involve an If - then condition.
Max_Current = Current_LSB ´ 32767
Max_Current = 0.06226
(15)
If Max_Current ≥ Max Possible_I then
Max_Current_Before_Overflow = MaxPossible_I
Else
Max_Current_Before_Overflow = Max_Current
End If
(Note that Max_Current is less than MaxPossible_I in this example.)
Max_Current_Before_Overflow = 0.06226 (Note: This result is displayed by software as seen in Figure 22.)
Max_ShuntVoltage = Max_Current_Before_Overflow ´ RSHUNT
Max_ShuntVoltage = 0.3113
(16)
If Max_ShuntVoltage ≥ VSHUNT_MAX
Max_ShuntVoltage_Before_Overflow = VSHUNT_MAX
Else
Max_ShuntVoltage_Before_Overflow= Max_ShuntVoltage
End If
(Note that Max_ShuntVoltage is less than VSHUNT_MAX in this example.)
Max_ShuntVoltage_Before_Overflow = 0.3113 (Note: This result is displayed by software as seen in
Figure 22.)
8. Compute the maximum power with equation 8.
MaximumPower = Max_Current_Before_Overflow ´ VBUS_MAX
MaximumPower = 1.992
(17)
9. (Optional second calibration step.) Compute the corrected full-scale calibration value based on measured
current.
INA219_Current = 0.06226
MeaShuntCurrent = 0.05
Corrected_Full_Scale_Cal = trunc
Cal ´ MeasShuntCurrent
INA219_Current
Corrected_Full_Scale_Cal = 3462
(18)
Figure 22 illustrates how to perform the same procedure discussed in this example using the automated
INA219EVM software. Note that the same numbers used in the nine-step example are used in the software
example in Figure 22. Also note that Figure 22 illustrates which results correspond to which step (for
example, the information entered in Step 1 is enclosed in a box in Figure 22 and labeled).
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Figure 22. Calibration Software Automatically Computes Calibration Steps 1-9
22
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REGISTER INFORMATION
The INA219 uses a bank of registers for holding
configuration
settings,
measurement
results,
maximum/minimum limits, and status information.
Table 2 summarizes the INA219 registers; Figure 12
illustrates registers.
Register contents are updated 4µs after completion of
the write command. Therefore, a 4µs delay is
required between completion of a write to a given
register and a subsequent read of that register
(without changing the pointer) when using SCL
frequencies in excess of 1MHz.
Table 2. Summary of Register Set
POINTER
ADDRESS
(1)
(2)
POWER-ON RESET
BINARY
HEX
TYPE (1)
All-register reset, settings for bus
voltage range, PGA Gain, ADC
resolution/averaging.
00111001 10011111
399F
R/W
Shunt voltage measurement data.
Shunt voltage
—
R
Bus voltage
—
R
Power measurement data.
00000000 00000000
0000
R
Current (2)
Contains the value of the current flowing
through the shunt resistor.
00000000 00000000
0000
R
Calibration
Sets full-scale range and LSB of current
and power measurements. Overall
system calibration.
00000000 00000000
0000
R/W
HEX
REGISTER NAME
00
Configuration Register
01
Shunt Voltage
02
Bus Voltage
03
Power (2)
04
05
FUNCTION
Bus voltage measurement data.
Type: R = Read-Only, R/W = Read/Write.
The Power Register and Current Register default to '0' because the Calibration Register defaults to '0', yielding a zero current value until
the Calibration Register is programmed.
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REGISTER DETAILS
All INA219 registers 16-bit registers are actually two 8-bit bytes via the I2C interface.
Configuration Register 00h (Read/Write)
BIT #
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
BIT
NAME
RST
—
BRNG
PG1
PG0
BADC4
BADC3
BADC2
BADC1
SADC4
SADC3
SADC2
SADC1
MODE3
MODE2
MODE1
POR
VALUE
0
0
1
1
1
0
0
1
1
0
0
1
1
1
1
1
Bit Descriptions
RST:
Reset Bit
Bit 15
Setting this bit to '1' generates a system reset that is the same as power-on reset. Resets all registers to default
values; this bit self-clears.
BRNG:
Bus Voltage Range
Bit 13
0 = 16V FSR
1 = 32V FSR (default value)
PG:
PGA (Shunt Voltage Only)
Bits 11, 12
Sets PGA gain and range. Note that the PGA defaults to ÷8 (320mV range). Table 3 shows the gain and range for
the various product gain settings.
Table 3. PG Bit Settings (1)
(1)
PG1
PG0
GAIN
RANGE
0
0
1
±40mV
0
1
÷2
±80mV
1
0
÷4
±160mV
1
1
÷8
±320mV
Shaded values are default.
BADC:
BADC Bus ADC Resolution/Averaging
Bits 7–10
These bits adjust the Bus ADC resolution (9-, 10-, 11-, or 12-bit) or set the number of samples used when
averaging results for the Bus Voltage Register (02h).
24
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SADC:
SADC Shunt ADC Resolution/Averaging
Bits 3–6
These bits adjust the Shunt ADC resolution (9-, 10-, 11-, or 12-bit) or set the number of samples used when
averaging results for the Shunt Voltage Register (01h).
BADC (Bus) and SADC (Shunt) ADC resolution/averaging and conversion time settings are shown in Table 4.
Table 4. ADC Settings (1)
ADC4
(1)
(2)
ADC3
ADC2
ADC1
0
X
(2)
0
0
9-bit
84µs
0
X (2)
0
1
10-bit
148µs
0
X (2)
1
0
11-bit
276µs
0
(2)
1
1
12-bit
532µs
1
0
0
0
12-bit
532µs
1
0
0
1
2
1.06ms
1
0
1
0
4
2.13ms
1
0
1
1
8
4.26ms
1
1
0
0
16
8.51ms
1
1
0
1
32
17.02ms
1
1
1
0
64
34.05ms
1
1
1
1
128
68.10ms
X
MODE/SAMPLES
CONVERSION TIME
Shaded values are default.
X = Don't care.
MODE:
Operating Mode
Bits 0–2
Selects continuous, triggered, or power-down mode of operation. These bits default to continuous shunt and bus
measurement mode. The mode settings are shown in Table 5.
Table 5. Mode Settings (1)
(1)
MODE3
MODE2
MODE1
MODE
0
0
0
Power-Down
0
0
1
Shunt Voltage, Triggered
0
1
0
Bus Voltage, Triggered
0
1
1
Shunt and Bus, Triggered
1
0
0
ADC Off (disabled)
1
0
1
Shunt Voltage, Continuous
1
1
0
Bus Voltage, Continuous
1
1
1
Shunt and Bus, Continuous
Shaded values are default.
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DATA OUTPUT REGISTERS
Shunt Voltage Register 01h (Read-Only)
The Shunt Voltage Register stores the current shunt voltage reading, VSHUNT. Shunt Voltage Register bits are
shifted according to the PGA setting selected in the Configuration Register (00h). When multiple sign bits are
present, they will all be the same value. Negative numbers are represented in two's complement format.
Generate the two's complement of a negative number by complementing the absolute value binary number and
adding 1. Extend the sign, denoting a negative number by setting the MSB = '1'. Extend the sign to any
additional sign bits to form the 16-bit word.
Example: For a value of VSHUNT = –320mV:
1. Take the absolute value (include accuracy to 0.01mV)==> 320.00
2. Translate this number to a whole decimal number ==> 32000
3. Convert it to binary==> 111 1101 0000 0000
4. Complement the binary result : 000 0010 1111 1111
5. Add 1 to the Complement to create the Two’s Complement formatted result ==> 000 0011 0000 0000
6. Extend the sign and create the 16-bit word: 1000 0011 0000 0000 = 8300h (Remember to extend the sign to
all sign-bits, as necessary based on the PGA setting.)
At PGA = ÷8, full-scale range = ±320mV (decimal = 32000, positive value hex = 7D00, negative value hex =
8300), and LSB = 10µV.
BIT #
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
BIT
NAME
SIGN
SD14_8
SD13_8
SD12_8
SD11_8
SD10_8
SD9_8
SD8_8
SD7_8
SD6_8
SD5_8
SD4_8
SD3_8
SD2_8
SD1_8
SD0_8
POR
VALUE
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
At PGA = ÷4, full-scale range = ±160mV (decimal = 16000, positive value hex = 3E80, negative value hex =
C180), and LSB = 10µV.
BIT #
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
BIT
NAME
SIGN
SIGN
SD13_4
SD12_4
SD11_4
SD10_4
SD9_4
SD8_4
SD7_4
SD6_4
SD5_4
SD4_4
SD3_4
SD2_4
SD1_4
SD0_4
POR
VALUE
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
At PGA = ÷2, full-scale range = ±80mV (decimal = 8000, positive value hex = 1F40, negative value hex = E0C0),
and LSB = 10µV.
BIT #
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
BIT
NAME
SIGN
SIGN
SIGN
SD12_2
SD11_2
SD10_2
SD9_2
SD8_2
SD7_2
SD6_2
SD5_2
SD4_2
SD3_2
SD2_2
SD1_2
SD0_2
POR
VALUE
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
At PGA = ÷1, full-scale range = ±40mV (decimal = 4000, positive value hex = 0FA0, negative value hex = F060),
and LSB = 10µV.
BIT #
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
BIT
NAME
SIGN
SIGN
SIGN
SIGN
SD11_1
SD10_1
SD9_1
SD8_1
SD7_1
SD6_1
SD5_1
SD4_1
SD3_1
SD2_1
SD1_1
SD0_1
POR
VALUE
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
26
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Table 6. Shunt Voltage Register Format (1)
VSHUNT
Reading (mV)
Decimal
Value
PGA = ÷ 8
(D15…..................D0)
PGA = ÷ 4
(D15…..................D0)
PGA = ÷ 2
(D15…..................D0)
PGA = ÷ 1
(D15…..................D0)
320.02
32002
0111 1101 0000 0000
0011 1110 1000 0000
0001 1111 0100 0000
0000 1111 1010 0000
320.01
32001
0111 1101 0000 0000
0011 1110 1000 0000
0001 1111 0100 0000
0000 1111 1010 0000
320.00
32000
0111 1101 0000 0000
0011 1110 1000 0000
0001 1111 0100 0000
0000 1111 1010 0000
319.99
31999
0111 1100 1111 1111
0011 1110 1000 0000
0001 1111 0100 0000
0000 1111 1010 0000
319.98
31998
0111 1100 1111 1110
0011 1110 1000 0000
0001 1111 0100 0000
0000 1111 1010 0000
160.02
16002
0011 1110 1000 0010
0011 1110 1000 0000
0001 1111 0100 0000
0000 1111 1010 0000
160.01
16001
0011 1110 1000 0001
0011 1110 1000 0000
0001 1111 0100 0000
0000 1111 1010 0000
160.00
16000
0011 1110 1000 0000
0011 1110 1000 0000
0001 1111 0100 0000
0000 1111 1010 0000
159.99
15999
0011 1110 0111 1111
0011 1110 0111 1111
0001 1111 0100 0000
0000 1111 1010 0000
159.98
15998
0011 1110 0111 1110
0011 1110 0111 1110
0001 1111 0100 0000
0000 1111 1010 0000
80.02
8002
0001 1111 0100 0010
0001 1111 0100 0010
0001 1111 0100 0000
0000 1111 1010 0000
80.01
8001
0001 1111 0100 0001
0001 1111 0100 0001
0001 1111 0100 0000
0000 1111 1010 0000
80.00
8000
0001 1111 0100 0000
0001 1111 0100 0000
0001 1111 0100 0000
0000 1111 1010 0000
79.99
7999
0001 1111 0011 1111
0001 1111 0011 1111
0001 1111 0011 1111
0000 1111 1010 0000
79.98
7998
0001 1111 0011 1110
0001 1111 0011 1110
0001 1111 0011 1110
0000 1111 1010 0000
40.02
4002
0000 1111 1010 0010
0000 1111 1010 0010
0000 1111 1010 0010
0000 1111 1010 0000
40.01
4001
0000 1111 1010 0001
0000 1111 1010 0001
0000 1111 1010 0001
0000 1111 1010 0000
40.00
4000
0000 1111 1010 0000
0000 1111 1010 0000
0000 1111 1010 0000
0000 1111 1010 0000
39.99
3999
0000 1111 1001 1111
0000 1111 1001 1111
0000 1111 1001 1111
0000 1111 1001 1111
39.98
3998
0000 1111 1001 1110
0000 1111 1001 1110
0000 1111 1001 1110
0000 1111 1001 1110
0.02
2
0000 0000 0000 0010
0000 0000 0000 0010
0000 0000 0000 0010
0000 0000 0000 0010
0.01
1
0000 0000 0000 0001
0000 0000 0000 0001
0000 0000 0000 0001
0000 0000 0000 0001
0
0
0000 0000 0000 0000
0000 0000 0000 0000
0000 0000 0000 0000
0000 0000 0000 0000
–0.01
–1
1111 1111 1111 1111
1111 1111 1111 1111
1111 1111 1111 1111
1111 1111 1111 1111
–0.02
–2
1111 1111 1111 1110
1111 1111 1111 1110
1111 1111 1111 1110
1111 1111 1111 1110
–39.98
–3998
1111 0000 0110 0010
1111 0000 0110 0010
1111 0000 0110 0010
1111 0000 0110 0010
–39.99
–3999
1111 0000 0110 0001
1111 0000 0110 0001
1111 0000 0110 0001
1111 0000 0110 0001
–40.00
–4000
1111 0000 0110 0000
1111 0000 0110 0000
1111 0000 0110 0000
1111 0000 0110 0000
–40.01
–4001
1111 0000 0101 1111
1111 0000 0101 1111
1111 0000 0101 1111
1111 0000 0110 0000
–40.02
–4002
1111 0000 0101 1110
1111 0000 0101 1110
1111 0000 0101 1110
1111 0000 0110 0000
–79.98
–7998
1110 0000 1100 0010
1110 0000 1100 0010
1110 0000 1100 0010
1111 0000 0110 0000
–79.99
–7999
1110 0000 1100 0001
1110 0000 1100 0001
1110 0000 1100 0001
1111 0000 0110 0000
–80.00
–8000
1110 0000 1100 0000
1110 0000 1100 0000
1110 0000 1100 0000
1111 0000 0110 0000
–80.01
–8001
1110 0000 1011 1111
1110 0000 1011 1111
1110 0000 1100 0000
1111 0000 0110 0000
–80.02
–8002
1110 0000 1011 1110
1110 0000 1011 1110
1110 0000 1100 0000
1111 0000 0110 0000
–159.98
–15998
1100 0001 1000 0010
1100 0001 1000 0010
1110 0000 1100 0000
1111 0000 0110 0000
–159.99
–15999
1100 0001 1000 0001
1100 0001 1000 0001
1110 0000 1100 0000
1111 0000 0110 0000
–160.00
–16000
1100 0001 1000 0000
1100 0001 1000 0000
1110 0000 1100 0000
1111 0000 0110 0000
–160.01
–16001
1100 0001 0111 1111
1100 0001 1000 0000
1110 0000 1100 0000
1111 0000 0110 0000
–160.02
–16002
1100 0001 0111 1110
1100 0001 1000 0000
1110 0000 1100 0000
1111 0000 0110 0000
–319.98
–31998
1000 0011 0000 0010
1100 0001 1000 0000
1110 0000 1100 0000
1111 0000 0110 0000
–319.99
–31999
1000 0011 0000 0001
1100 0001 1000 0000
1110 0000 1100 0000
1111 0000 0110 0000
–320.00
–32000
1000 0011 0000 0000
1100 0001 1000 0000
1110 0000 1100 0000
1111 0000 0110 0000
–320.01
–32001
1000 0011 0000 0000
1100 0001 1000 0000
1110 0000 1100 0000
1111 0000 0110 0000
–320.02
–32002
1000 0011 0000 0000
1100 0001 1000 0000
1110 0000 1100 0000
1111 0000 0110 0000
(1)
Out-of-range values are shown in grey shading.
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Bus Voltage Register 02h (Read-Only)
The Bus Voltage Register stores the most recent bus voltage reading, VBUS.
At full-scale range = 32V (decimal = 8000, hex = 1F40), and LSB = 4mV.
BIT #
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
BIT
NAME
BD12
BD11
BD10
BD9
BD8
BD7
BD6
BD5
BD4
BD3
BD2
BD1
BD0
—
CNVR
OVF
POR
VALUE
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
At full-scale range = 16V (decimal = 4000, hex = 0FA0), and LSB = 4mV.
BIT #
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
BIT
NAME
0
BD11
BD10
BD9
BD8
BD7
BD6
BD5
BD4
BD3
BD2
BD1
BD0
—
CNVR
OVF
POR
VALUE
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
CNVR:
Conversion Ready
Bit 1
Although the data from the last conversion can be read at any time, the INA219 Conversion Ready bit (CNVR)
indicates when data from a conversion is available in the data output registers. The CNVR bit is set after all
conversions, averaging, and multiplications are complete. CNVR will clear under the following conditions:
1.) Writing a new mode into the Operating Mode bits in the Configuration Register (except for Power-Down or
Disable)
2.) Reading the Power Register
OVF:
Math Overflow Flag
Bit 0
The Math Overflow Flag (OVF) is set when the Power or Current calculations are out of range. It indicates that
current and power data may be meaningless.
Power Register 03h (Read-Only)
Full-scale range and LSB are set by the Calibration Register. See the Programming the INA219 Power
Measurement Engine section.
BIT #
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
BIT
NAME
PD15
PD14
PD13
PD12
PD11
PD10
PD9
PD8
PD7
PD6
PD5
PD4
PD3
PD2
PD1
PD0
POR
VALUE
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
The Power Register records power in watts by multiplying the values of the current with the value of the bus
voltage according to the equation:
Current ´ BusVoltage
Power =
5000
Current Register 04h (Read-Only)
Full-scale range and LSB depend on the value entered in the Calibration Register. See the Programming the
INA219 Power Measurement Engine section. Negative values are stored in two's complement format.
BIT #
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
BIT
NAME
CSIGN
CD14
CD13
CD12
CD11
CD10
CD9
CD8
CD7
CD6
CD5
CD4
CD3
CD2
CD1
CD0
POR
VALUE
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
The value of the Current Register is calculated by multiplying the value in the Shunt Voltage Register with the
value in the Calibration Register according to the equation:
Current =
28
ShuntVoltage ´ Calibration Register
4096
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CALIBRATION REGISTER
Calibration Register 05h (Read/Write)
Current and power calibration are set by bits D15 to D1 of the Calibration Register. Note that bit D0 is not used in
the calculation. This register sets the current that corresponds to a full-scale drop across the shunt. Full-scale
range and the LSB of the current and power measurement depend on the value entered in this register. See the
Programming the INA219 Power Measurement Engine section. This register is suitable for use in overall system
calibration. Note that the '0' POR values are all default.
BIT #
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0 (1)
BIT
NAME
FS15
FS14
FS13
FS12
FS11
FS10
FS9
FS8
FS7
FS6
FS5
FS4
FS3
FS2
FS1
FS0
POR
VALUE
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
(1)
D0 is a void bit and will always be '0'. It is not possible to write a '1' to D0. CALIBRATION is the value stored in D15:D1.
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PACKAGE OPTION ADDENDUM
www.ti.com
22-Sep-2008
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
75
TBD
Lead/Ball Finish
Call TI
MSL Peak Temp (3)
INA219AID
PREVIEW
SOIC
D
8
INA219AIDCNR
ACTIVE
SOT-23
DCN
8
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Call TI
Level-2-260C-1 YEAR
INA219AIDCNRG4
ACTIVE
SOT-23
DCN
8
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
INA219AIDCNT
ACTIVE
SOT-23
DCN
8
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
INA219AIDCNTG4
ACTIVE
SOT-23
DCN
8
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
INA219AIDR
PREVIEW
SOIC
D
8
2500
TBD
Call TI
Call TI
(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)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
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provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
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