1.4W mono into 4Ω — the load-driving spec
The MAX9718AEUB+ is a Class AB mono amplifier rated for 1.4W continuous output into a 4Ω load from a single supply rail. That 1.4W figure is the headline parametric — it tells you the speaker impedance and the thermal budget the exposed-pad package must shed. For a portable speaker or a line-output stage driving a small transducer, 1.4W is enough for audible alert tones or voice playback without an external heatsink.
Operating from 2.7V to 5.5V, the amplifier runs directly off a single Li-ion cell (3.6V nominal) or a regulated 3.3V or 5V rail. Differential inputs reject common-mode noise picked up on long traces between the codec and the amp — useful when the audio source is on a separate board. The shutdown pin pulls the quiescent current to near zero for battery-powered sleep modes, and the depop circuit suppresses the turn-on thump that would otherwise couple into the speaker.
Package and thermal path
The 0.118-inch body width (3.00 mm) is standard for MSOP-10; the exposed pad adds roughly 2×2 mm of copper area under the part. Layout should connect the pad to the ground plane with multiple vias — the datasheet's recommended footprint is the reference.
ROHS3 compliant, so it passes EU material restrictions without an exemption.