INA700 datasheet(11/43 Pages) TI

11 / 43 page

Q1 =

i1 x t1

Q.. =

i.. x t..

Q.. =

i.. x t..

Q.. =

i.. x t..

Q.. =

i.. x t..

E.. =

p.. x t..

E.. =

p.. x t..

E.. =

p.. x t..

E.. =

p.. x t..

E1 =

p1 x t2

Power register

Energy register

Charge register

ADC,

Temperature, Current,

Voltage

Figure 7-5. Power, Energy and Charge Calculation Scheme

7.3.5 High-Precision Delta-Sigma ADC

The integrated ADC is a high-performance, low-offset, low-drift, delta-sigma ADC designed to support

bidirectional current flow. The measured inputs are selected through the high-voltage input multiplexer to

the ADC inputs as shown in Figure 7-4. 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 setting in the ADC_CONFIG register permit selecting modes

to convert only the current or bus voltage to further 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

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 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

www.ti.com

INA700

SBOSAB4 – MAY 2023

Submit Document Feedback

Product Folder Links: INA700

INA700 Datasheet(PDF) 11 Page - Texas Instruments

INA700 Datasheet(HTML) 11 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

Datasheet Download

Link URL