12amplifier BH3547F amplifying, then output two ways. One way will be sent to earphone, anotherway will be sent to digital sound amplifier R2A15112FP amplifying then sent to speaker.5. HDMI signal flowThree HDMI video signals via switcher PS321 are directly fed to the master control IC MSD109 todigital decode, image scale and OSD superposition, then output LVDS drive level for panel display.HDMI audio signal via decoder built-in MSD109 is fed to back end to bass adjust and volumecontrol, the sound will separate into L/R channels and input to earphone amplifier BH3547Famplifying, then output two ways. One way will be sent to earphone, another way will be sent todigital sound amplifier R2A15112FP amplifying then sent to speaker.Block diagram

Sanyo LCD-37XR8DA Service Manual