1W mono into 8Ω — what the output rating means for fit
The LM4889MM/NOPB delivers 1W continuous into an 8Ω load from a single supply rail — this is the maximum output power before clipping at 1% THD+N. For a portable speaker or headphone driver, that 1W is enough to drive an 8Ω speaker to moderate listening levels; the actual loudness depends on the speaker's sensitivity (dB SPL per watt). The supply range spans 2.2V to 5.5V, so a single Li-ion cell (3.6V nominal) or a 5V USB rail both work without an extra regulator. At the low end, the output swing is supply-limited — expect about 0.7W into 8Ω at 3.6V.
Housed in an 8-VSSOP (3.00mm × 3.00mm, 0.65mm pitch), the LM4889MM/NOPB fits tight portable layouts. The shutdown pin (active-low) pulls the supply current to under 1 µA, letting the host MCU gate the amplifier when no audio is playing. The depop circuit suppresses the turn-on thump that otherwise couples into the speaker.
Active lifecycle — sourcing posture
Sourced to order through independent distribution; availability and current pricing confirmed at RFQ against your BOM quantity.