Datasheet

Power=
Current BusVoltage´
5000
Current=
ShuntVoltage CalibrationRegister´
4096
INA219
SBOS448F –AUGUST 2008– REVISED SEPTEMBER 2011 www.ti.com
Bus Voltage Register 02h (Read-Only)
The Bus Voltage Register stores the most recent bus voltage reading, V
BUS
.
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
BD12 BD11 BD10 BD9 BD8 BD7 BD6 BD5 BD4 BD3 BD2 BD1 BD0 — CNVR OVF
NAME
POR
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
VALUE
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
0 BD11 BD10 BD9 BD8 BD7 BD6 BD5 BD4 BD3 BD2 BD1 BD0 — CNVR OVF
NAME
POR
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
VALUE
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
PD15 PD14 PD13 PD12 PD11 PD10 PD9 PD8 PD7 PD6 PD5 PD4 PD3 PD2 PD1 PD0
NAME
POR
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
VALUE
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 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
CSIGN CD14 CD13 CD12 CD11 CD10 CD9 CD8 CD7 CD6 CD5 CD4 CD3 CD2 CD1 CD0
NAME
POR
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
VALUE
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:
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