Current-sense amp for a 26V rail — what the ratings mean on the bench
The INA381A4IDGSR is a Zero-Drift current-sense amplifier from Texas Instruments, designed to measure current by sensing the voltage drop across a shunt resistor on either the high side or low side of the supply rail. Its input voltage range of 0V to 26V covers common 12V and 24V industrial rails, plus some 5V and 3.3V circuits — the 26V ceiling means it handles a 24V nominal supply with margin for transients without needing an external clamp. The ±1% accuracy figure is the total error over the full temperature range, not just at 25°C — for a 10A load on a 10mΩ shunt, that 1% translates to ±100mA of uncertainty in the current reading, which is tight enough for overcurrent detection and battery monitoring.
Board-fit and temperature grade
Housed in a 10-VSSOP package (3.00mm width), this is a fine-pitch surface-mount part that reflows with a standard lead-free profile — no special stencil or underfill required for most production lines. The -40°C to 125°C operating range qualifies it for under-hood automotive, industrial motor drives, and outdoor telecom gear where the ambient temperature inside the enclosure can hit 85°C or higher.
Fully ROHS3 compliant, so it ships without any of the six restricted substances plus the four phthalates — no exemption stickers needed on the final assembly.
