Dual current-sense amplifier for precision monitoring
The Analog Devices MAX4377FAUA+ is a dual current-sense amplifier in an 8-uMAX/uSOP surface-mount package. It integrates two independent current-sense circuits, each drawing 1 mA supply current, making it suited for multi-rail monitoring in a compact footprint. The amplifier operates from a 3 V to 28 V supply span, covering common 5 V and 12 V power rails without an extra regulator. Its -40°C to 125°C temperature range qualifies it for industrial and automotive environments such as motor drives, outdoor telecom, and engine-bay electronics.
Bandwidth and slew rate — what they mean for your measurement
The 2 MHz -3 dB bandwidth sets the upper frequency of current signals the amplifier can faithfully reproduce. For a 12 V rail switching at 500 kHz, this gives enough margin to capture the average current without significant attenuation. A 10 V/µs slew rate means the output can swing from 0 V to 5 V in 500 ns, which is fast enough to respond to overcurrent events in a typical power-stage protection loop. The 120 µA input bias current is a design consideration when using high-value sense resistors — it adds a small offset voltage across the sense element.
Package and supply — board-fit details
The MAX4377FAUA+ comes in an 8-TSSOP / 8-MSOP (0.118", 3.00 mm width) package, supplied in Tube. The supplier device package is 8-uMAX/uSOP, which is the same footprint as a standard MSOP-8. Surface-mount assembly is straightforward with standard reflow profiles.
Lifecycle and compliance
It is ROHS3 compliant, so it meets current European RoHS requirements without exemption. For new designs, this part carries no imminent LTB risk.