The amp is stereo efficient, digital amplifier power stage for driving speakers up to 2x30W/8Ω. The high efficiency of the amp allows it to do 2x30W/8Ω without external heat sink. This module has standby and mute function, so Arduino can control it how and when it works. Features: Volume control Audio output (L/R) Audio input Mute interface 3.5 earphone input Power supply Specification: SNR 90(db) DR 0.01% Input impedance@ Voltage 3Ω@6V-19V 8Ω@6V-24V size 60mm*55mm*15mm 25W + 25W continuous output power at THD = 10% with RL = 8 Ω and VCC = 26 V Wide-range single-supply operation (4.5 - 26 V) High efficiency (η = 90%) Four selectable, fixed gain settings of nominally 20dB, 26dB, 32dB, and 36dB Differential inputs minimize common-mode noise Standby and mute features Short-circuit protection Thermal overload protection Externally synchronizable ECOPACK®, environmentally-friendly package Technology support：support@sbote.com