Raising the power supply to 5v @ 300 mA in my next try. Thank you for your advice.There are several class-D amplifier ICs specifically designed for low supply voltages.
Go to the TI, OnSemi, NXP, STMicro webpages and using the parametric tools select a device that suits your needs and budget.
But if you have the 5v @ 200 mA supply limitations, even with a class-D your output power will be below 1 watt. Simple physics laws.
Hi Audioguru,The LM386 works fine when it is powered from a new 9V battery and you keep the output into an 8 ohms speaker below 0.45W. Using a higher supply voltage and/or a lower speaker impedance simply makes the LM386 heat more with almost the same output power.
The TS4890 produces only 0.2W into an 8 ohm speaker when its supply is 2.2V. You might need to hold the speaker close to you to hear it.
Why are you using the very complicated Demo circuit (the output capacitors are not needed to feed the speaker)?
Texas Instruments have many modern amplifier ICs.
If the mic can hear the speaker then you will have acoustical howling feedback.