INA745AIRELR datasheet(14/50 Pages) TI2

14 / 50 page

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____ Input Current Step

____ ADC Current Output

Figure 6-3. Device Current Transient Overshoot

The transient overshoot is similar to what is observed in analog output current sense amplifiers. Understanding

that this overshoot occurs when setting an overcurrent alert threshold to avoid false triggers is important.

6.3.2 Safe Operating Area

The heat generated by the device power dissipation limits the maximum current that can be safely handled by

the package. The current consumed to power the device is low, therefore the primary source of heating is due

to the current flow through the internal shunt resistor. The maximum safe-operating current level shown in Figure

6-4 is set to verify that the heat generated in the package is limited so that the internal junction temperature of

the silicon does not exceed 150°C. This data is collected on the INA745x evaluation module (SENS109A).

Figure 6-4. Maximum Continuous Shunt Current vs Ambient Temperature

Even though the shunt can withstand currents greater than 35A, the current measurement capability is limited by

ADC full scale range of 39.32A. The ADC full scale range is also a function of temperature (see Figure 8-1).

In applications with overcurrent transients, the peak amplitude and duration of the overcurrent event is important

to determine the device heating. Figure 6-5 shows the peak pulse current versus pulse duration that the device

can withstand before the maximum junction temperature of 150°C is exceeded. The data shown in this curve is

collected at TA =-40°C, 25°C, and 125°C using the INA745x evaluation module (SENS109A).

INA745A, INA745B

SBOSAC3B – JULY 2023 – REVISED AUGUST 2025

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INA745AIRELR 数据表(PDF) 14 Page - Texas Instruments