Cirrus Logic CDB48500-USB, Manual, Page: 19 / 52

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©
Copyright 2008 Cirrus Logic , Inc. DS784DB1
CDB48500 System Block Descriptions
CDB485x00-USB Evaluation Kit Guide
3.1.2.2 Headphone Output
• Connector Type: 1/8” TRS Female
• Full Scale Amplitude: 3.53 V
RMS
• Reference Designator: J20, or HP_OUT
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.