Overview
The LC75391 and LC75391M are single-chip electronic volume and tone control systems that support volume control, tone control, and input and output signal switching functions controlled by serial input data.

Functions
• Input and output signal switching: The four I/O switches can be set to on or off independently.
• Volume control: Independent control of the left and right channels can be used to implement a balance function. 0 to –20 dB in 2 dB steps, –20 to –32 dB in 3 dB steps, –32 to –53 dB in 4 dB steps, –52 to –70 dB in 4.5 dB steps, and –∞.
• Tone controls: Four frequency characteristic types selectable by setting internal switches. Also supports a buffer function that requires no external components.
• Two general-purpose output ports: These ports allow this LSI to control motorized volume controls and general-purpose logic.