Active production — what it means for the BOM line
For a BOM that already carries the LM4980SD/NOPB, this means no forced redesign or substitute qualification is needed — the line can be replenished through normal supply routes.
Headroom for portable audio: 42 mW into 16 Ω
Rated 42 mW per channel into a 16 Ω load, this Class AB amplifier delivers enough output to drive consumer headphones to listenable levels from a single Li-ion cell.
Package and rework: 10-WSON with exposed pad
The 10-WFDFN exposed pad package, also designated 10-WSON (3x3 mm), has a central thermal pad that must be soldered to a PCB copper plane for heat sinking. The pad also anchors the part — without a good solder joint under it, the package can shift during reflow. For hand rework, preheat the board to 100-120°C before hitting the WSON with hot air. The exposed pad soaks up heat fast; a bottom-side preheat keeps the part from cooling the pad and causing a cold joint.
Built-in pop suppression and thermal shutdown
The depop feature suppresses turn-on/turn-off clicks by ramping the output bias, which matters in battery-powered devices where the amplifier is frequently shut down to save power. The shutdown pin lets a GPIO cut supply current to near zero between audio bursts. Thermal protection folds back output drive if the die temperature exceeds the safe limit — a safeguard if the headphone jack is shorted or the output is driven into a low-impedance load continuously.