Class AB mono amplifier with 1.25 W into 8 Ω
The Texas Instruments TPA6205A1DRBR is a Class AB mono audio amplifier delivering 1.25 W into an 8 Ω load from a single supply rail. It runs off 2.5 V to 5.5 V.
What the ratings mean for your BOM
1.25 W at 8 Ω is the headline number — that is enough for a small speaker in a portable radio, a Bluetooth speaker, or an alert tone generator. The 2.5 V minimum supply means it runs directly from a single Li-ion cell without a boost converter. The -40°C to 85°C temperature range covers outdoor and industrial use; no need to derate for a hot enclosure. Built-in depop circuitry suppresses power-up clicks, so you can skip the external mute transistor. Differential inputs reject ground noise on long input traces. Shutdown pin lets a microcontroller cut supply current to near zero between audio bursts — useful for battery life. Thermal protection saves the part if the output clips into a short.