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Texas Instruments LM4673SD/NOPB — Analog & Data Acquisition

LM4673SD/NOPB TI Class D Audio Amp, 2.65W into 4Ω

MPNLM4673SD/NOPB
End of Life

Texas Instruments LM4673SD/NOPB, Boomer®/PowerWise® series, Class D mono audio amplifier, 2.65W x 1 @ 4Ω, 2.4V–5.5V supply, -40°C–85°C, 8-WSON (3x3) exposed pad package.

$2.0Ref. price · indicative, final on quote
Packaging8-WFDFN Exposed Pad
RoHSROHS3 Compliant
SeriesBoomer®, PowerWise®
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

LM4673SD/NOPB specifications
ParameterValue
TypeClass D
SeriesBoomer®, PowerWise®
Output type1-Channel (Mono)
MountingSurface Mount
Supply voltage2.4V ~ 5.5V
Max output power x channels @ load2.65W x 1 @ 4Ohm
Operating temperature-40°C ~ 85°C (TA)
PackageTape & Reel (TR); Cut Tape (CT)
FeaturesDepop, Differential Inputs, PWM, Short-Circuit and Thermal Protection, Shutdown
Case8-WFDFN Exposed Pad

Product details

Class D mono amplifier rated for 2.65 W into 4 Ω

The Texas Instruments LM4673SD/NOPB is a Class D mono audio amplifier from the Boomer® and PowerWise® series, delivering 2.65 W into a 4 Ω load from a single supply. Supply range spans 2.4 V to 5.5 V.

That 2.65 W into 4 Ω is the maximum output power per channel at the rated load. For a portable speaker or soundbar channel, this delivers enough volume for a small enclosure without an external heatsink — the exposed pad on the 8-WSON (3x3) package pulls heat into the PCB copper. If your design needs more headroom, you step up to a higher-power Boomer® part; if efficiency at low volume matters more, the Class D topology already beats a linear Class AB on battery life.

No last-time-buy or phase-out notice is on record. The part is fully ROHS3 compliant, so it meets current European and global material restrictions without exemption paperwork.

Package and mounting — 8-WSON with exposed pad

The 8-WSON exposed-pad package (3x3 mm) is a surface-mount footprint. No through-hole option exists.

Frequently asked questions

What is the difference between LM4673SD and LM4673SD/NOPB?

The /NOPB suffix indicates ROHS3 compliance (lead-free). The LM4673SD without the suffix is the older, non-ROHS version. Electrically they are identical; the /NOPB is the current production variant.

What is the typical output power of LM4673SD/NOPB into 4 ohms?

The maximum output power is 2.65 W into a 4 Ω load from a single channel.