The Tiny Audio Amplifier kit is a good choice for battery operation. It is based on LM386 IC.
Specifications
Power supply – 6 – 12 VDC
Output power – 1 W, 8 Ohm
The quiescent power drain is only 24 mW when operating from 6 VDC
Self-centering output quiescent voltage
Onboard PRESET to adjust volume
Terminal pins for connecting power supply, audio signal and speaker
Power-On LED indicator
ON/OFF PCB mounted slide switch for power supply
Four mounting holes of 3.2 mm each
PCB dimensions 44 mm x 44 mm
Schematic
Parts
Inputs – Outputs configuration
PCB
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