Data Sheet

4D SYSTEMS SOMO-II

SOMO

-II Embedded Audio

-Sound Module

KEY MODE - Example Connection Diagram

This is an example schematic showing the simplest connections to the SOMO-II for KEY MODE. Only 2 buttons

are required. NEXT/VOL+ will start playing a track if currently stopped, and will raise the volume if the button is

held down for > 1.2 seconds. PRE/VOL- will start playing a track if currently stopped also, and will lower the

volume if the button is held down for > 1.2 seconds. See the table in Section 5.3 for more information.

For a comprehensive control of the SOMO-II in KEY MODE, the buttons listed in 5.4 are connected to pins 5

and 6 in the schematic shown above.

The example schematic also illustrates the connections for both Mono Speaker connection, along with Stereo

DAC for either headphones or an external amplifier. If the gain is too high for the chosen application when

using the Stereo DAC outputs, a 100ohm resistor can be put in series between the external device and pin 14,

along with another 100ohm resistor in series between the external device and pin 13. This will reduce the gain.

Other values may be more suitable.