Using the M5Stack Core speaker

The M5Stack Core speaker allows the programmable unit to be transformed into a portable creative sound generator. The M5Stack Core speaker is driven by a powerful 3W class D amplifier. The benefit of using this type of amplifier is its efficiency. Theoretical class D amplifiers have an operational efficiency of 100%. Typically, a class D amplifier has an efficiency of 90%. This high-efficiency rating is achieved by switching the amplifier’s output transistors instead of driving them linearly. A pulse width modulation (PWM) signal effect is created, thus reducing the output transistors’ thermal dissipation. Further, this output switching produces a high voltage and current amplification signal. With a reduction in thermal dissipation, the efficiency of the output transistors driving a speaker is highly effective. Figure 3.14 shows a block diagram of the M5Stack Core speaker-amplifier circuit:

Figure 3.14 –...