Class AB stereo amp with headphone drive
The LM4838MTEX/NOPB is a Texas Instruments Boomer® Class AB audio amplifier delivering 2.2W per channel into 3Ω loads and 95mW per channel into 32Ω headphones — the dual output stage lets a single IC drive both speakers and a headphone jack without a separate headphone amp. Supply range is 2.7V to 5.5V, so it runs directly from a single Li-ion cell or a 3.3V/5V rail without an extra regulator. The 28-HTSSOP package with exposed pad (PowerPAD) needs a thermal via pattern under the pad to pull heat into the ground plane — without it the 2.2W output into 3Ω pushes the junction above the 85°C ambient limit.
Pop-free startup and thermal protection
Integrated depop circuitry ramps the output bias voltage at startup, which suppresses the audible thump that otherwise hits the speaker when the supply rail comes up. The mute pin lets a microcontroller hold the outputs at zero until the system is ready — useful in multi-zone audio where one channel must stay silent during a DSP boot sequence. Thermal protection shuts the amplifier down if the die temperature exceeds the safe limit — the part auto-recovers when it cools, so a shorted speaker lead on a hot bench does not permanently damage the IC. The shutdown pin also allows a low-power sleep state for battery-powered gear.
Active production, RoHS3, industrial temp
It is ROHS3 compliant, so it passes into EU and UK markets without an exemption declaration. The -40°C to +85°C operating range covers industrial and outdoor equipment, not just consumer audio. Supplied in Tape & Reel — the 28-HTSSOP body is 4.40 mm wide, which feeds through standard 12 mm embossed carrier tape without a changeover on most pick-and-place lines. The exposed pad requires a solder paste stencil aperture that covers 50-70% of the pad area; a full-coverage stencil risks voiding under the die attach pad.