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3 optical digital output (pcm), 3 dc power input, 4 control header – Cirrus Logic CDB48500-USB User Manual

Page 17: 5 on-board voltage selection headers, 3 optical digital output (pcm) -3

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3.1.2.3 Optical Digital Output (PCM)

Connector Type: Fiber Optic TX for Digital Audio, JIS F05 (JIS C5974-1993 F05)

Reference Designator: J24, or SPDIF_TX

The S/PDIF output uses the same data line as AOUT_4A and AOUT_4B. When the digital output has been
enabled, and you have speakers connected to AOUT_4A and AOUT_4B white noise will be heard. This could
damage the speakers.

3.1.3 DC Power Input

Voltage Range: +9V

DC

TO

+12V

DC

Minimum Power: 8W supply

Connector Type: 2mm Female, positive center pin

Reference Designator: J25

3.1.4 Control Header

Connector Type: 2x25, 0.100 inch Shrouded Male

Reference Designator: J11

This connector is the interface between the CDB48500 and the CDB USB MASTER. Control signals, clocks,
data, and +3.3V power are passed across this connector.

3.1.5 On-Board Voltage Selection Headers

Connector Type: 1x3, 0.100 inch, Stake Header

Reference Designator: J17 - J19

The CDB48500-USB is designed to operate from a single DC power input. The 9V power supply provided with
the kit is connected to the DC power input jack (J25) and is regulated down to the system voltages (5V, 3.3V,
1.8V). The power selection headers should be set to the ‘REG’ position when using the DC wall supply. This is
the default mode of operation and should not need to be changed for most applications.

It is possible to bypass the regulated power supplies for any of the voltages by removing the jumper from the
appropriate power selection header, and connecting an external voltage supply to the center pin of that selection
header.

The third configuration for the power selection headers is the ‘EXT’ position. This is a special mode of operation,
and cannot be used while connected to the CDB USB MASTER control board. Placing the power selection
headers in the ‘EXT’ position while connected to the CDB USB MASTER will prevent the board from operating.

The unpopulated header, J3, is also designed for a special mode that brings 12V from the control header, but
cannot be used when connected to the CDB USB MASTER.