What this current-sense amp is built for
The MAX4390EUK-T: Its 500 V/µs slew rate and 72 MHz -3 dB bandwidth make it one of the faster options in this footprint — useful for sensing fast load transients or switching waveforms where a slower amplifier would smear the signal. The rail-to-rail output lets it swing close to the supply rails, which matters when the sense voltage is small and you need every millivolt of headroom. Supply span runs from 4.5 V up to 11 V, so it fits common 5 V and 10 V rails without a secondary regulator.
Package and mounting
The 500 V/µs slew rate is the standout number here. For a current-sense amplifier in a SOT-23-5, that is fast enough to track the rising edge of a short-circuit current or a PWM inductor ramp without significant delay. The 72 MHz bandwidth supports sensing in high-frequency switching converters or Class-D amplifier outputs. If you are monitoring DC currents only, a slower, lower-power part would do — but if the design needs to capture the shape of the current waveform, this part earns its place.
Package and supply reality
Input offset 5 mV, input bias current 2.5 µA. Output 55 mA.