Tiny stereo audio amplifier board has been designed around SMD TDA7266D IC from ST. The TDA7266D is a dual bridge amplifier specially designed for Portable Audio, LCD TV/Monitor, PC Motherboard, and TV applications. This circuit provides high quality audio output of 3W approx. on each channel with standard audio signal input. The circuit works with 3.5V to 5V. Due to low supply input this amplifier is suitable for small size audio gadgets and portable audio applications like MP3 player, Voice messaging system, Warning signals, Annunciator etc.
Specifications
- Supply voltage range 3.5 to 5v (maximum supply 5v due to small pcb and small thermal area)
- Output power 3+3w @thd = 10%, rl = 8ω, vcc = 3.7v (3w approx.)
- Single supply
- Minimum external components no svr capacitor no bootstrap no boucherot cells internally fixed gain
- Mute functions (jumper close)
- Short circuit protection
- Thermal overload protection
3W Stereo Audio Amplifier using TDA7266D – [Link]
With a 5Vsupply this TDA7266 amplifier IC cannot produce anywhere near 3W per channel into 8 ohms.
The datasheet shows a graph of output power into 8 ohms per channel at various supply voltages. With a 5V supply the output power is about 1W with low distortion or about 1.5W with horrible 10% distortion. It needs a supply of 8V to produce 3W per channel with low distortion or needs 7V with horrible 10% distortion.