INA700 datasheet(16/50 Pages) TI

16 / 50 page

the ADC inputs as shown in Figure 7-5. The ADC architecture enables lower drift measurement across

temperature and consistent offset measurements across the common-mode voltage, temperature, and power

supply variations. A low-offset ADC is preferred in current sensing applications to provide a near 0-V offset

voltage that maximizes the useful dynamic range of the system.

The INA700 measures the die temperature, current, and bus voltage. An internal temperature measurement is

made before each current measurement. Temperature compensation is then applied to the current measurement

to achieve low drift performance. The MODE bits in the ADC_CONFIG register permit selecting modes to

convert only the current or bus voltage to allow the user to configure the monitoring function to fit the specific

application requirements. After an ADC conversion is complete, the converted values independently update in

their corresponding registers where they can be read through the digital interface at the time of conversion end

if no averaging is selected. The conversion time for shunt voltage, bus voltage, and temperature inputs are set

independently from 50 µs to 4.12 ms depending on the values programmed in the ADC_CONFIG register. The

value for current is calculated after both the temperature and shunt voltage measurements are made. The total

time to get the current measurement is the sum of the conversion times for these two parameters. Enabled

measurement inputs are converted sequentially, which means the total time to convert all inputs depends on

the conversion time for each input and the number of inputs enabled. When averaging is used, the intermediate

values are subsequently stored in an averaging accumulator, and the conversion sequence repeats until the

number of averages is reached. After all of the averaging is complete, the final values are updated in the

corresponding registers that can then be read. These values remain in the data output registers until they are

replaced by the next fully completed conversion results. In this case, reading the data output registers does not

affect a conversion in progress.

The ADC has two conversion modes—continuous and triggered—set by the MODE bits in the ADC_CONFIG

the output registers as described above in an indefinite loop. In triggered-conversion mode, the ADC will convert

the input measurements as described above, after which the ADC will go into shutdown mode until the user

writes to the MODE bits to generate another single-shot trigger. Writing the MODE bits will interrupt and restart

triggered or continuous conversions that are in progress. Although the device can be read at any time, and

the data from the last conversion remains available, the Conversion Ready flag (CNVRF bit in ALERT_DIAG

are complete.

The Conversion Ready flag (CNVRF) clears under these conditions:

• Writing to the ADC_CONFIG register (except for selecting shutdown mode); or

• Reading the ALERT_DIAG Register

While the INA700 device is used in either one of the conversion modes, a dedicated digital engine is calculating

the current, power, charge and energy values in the background (see Internal Measurement and Calculation

Engine). In triggered mode, the accumulation registers (ENERGY and CHARGE) are invalid, as the device does

not keep track of elapsed time. For applications that require critical measurements in regards to accumulation of

time for energy and charge measurements, the device must be configured to use continuous conversion mode,

as the accumulated results are continuously updated and can provide true system representation of charge and

energy consumption in a system. All of the calculations are performed in the background and do not contribute to

conversion time.

For applications that must synchronize with other components in the system, the INA700 conversion can be

delayed by programming the CONVDLY bits in CONFIG register in the range between 0 ms (no delay) and 510

ms. The resolution in programming the conversion delay is 2 ms. The conversion delay is set to 0 by default.

Conversion delay can assist in measurement synchronization when multiple external devices are used for

voltage or current monitoring purposes. In applications where time aligned voltage and current measurements

are needed, two devices can be used with the current measurement delayed such that the external voltage and

current measurements will occur at approximately the same time. Keep in mind that even though the internal

time base for the ADC is precise, synchronization will be lost over time due to internal and external time base

mismatch.

INA700

SBOSAB4A – MAY 2023 – REVISED SEPTEMBER 2023

www.ti.com

Submit Document Feedback

Product Folder Links: INA700

INA700 датащи(PDF) 16 Page - Texas Instruments

INA700 датащи(HTML) 16 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

датащи скачать

ссылки URL