6.7W mono Class D in a 4x5 mm QFN
The Texas Instruments LM48511SQX/NOPB is a Boomer® series Class D audio amplifier delivering 6.7W into a 4Ω load from a single mono channel.
Supply range and load — what drives the BOM decision
The 3V to 5.5V supply range covers both regulated 3.3V rails in portable designs and direct 5V USB or battery lines. At 4Ω the amplifier hits its rated 6.7W maximum; into 8Ω the output drops proportionally, but the Class D efficiency (typically >85% at moderate power) keeps heatsinking minimal. The differential inputs reject ground noise common in single-supply layouts, and the depop feature suppresses the turn-on thump that otherwise needs an external mute circuit.
Protection set for production robustness
Short-circuit and thermal protection are integrated, so a speaker-wire short or a stalled fan in an enclosure won't cascade into a board-level failure. The shutdown pin lets a system controller put the amplifier into a low-power idle — useful for power-conscious designs where the amp is off when no audio is playing.
The "NOPB" suffix confirms lead-free / RoHS3 — no separate waiver or special handling needed for EU or California markets.