Inside the miniature chip is a class D controller, able to run from 2.0V-5.5VDC. This super small mono amplifier is surprisingly powerful – able to deliver up to 2.5 Watts into 4-8 ohm impedance speakers. 2130 Mono 2.5W Class D Audio Amplifier – PAM8302 module Mono 2.5W Class D Audio Amplifier – PAM830