ZEUS Technical Manual | Detailed hardware description |
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Audio
A Wolfson WM9712L AC’97 audio CODEC is used to support the audio features of the ZEUS. Audio inputs supported by the WM9712L are stereo line in and a mono microphone input.
The WM9712L provides a stereo line out that is amplified by a National Semiconductor
LM4880 250mW per channel power amplifier, suitable for driving an 8Ω load. The WM9712L AC’97 codec may be turned off if it is not required. See the section Audio power management, page 71, for details.
Connection to the ZEUS audio features is via header J4.
See the section J4 – Audio connector, page 79, for connector and mating connector details. The table below shows pin assignments:
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Function | Pin | Signal | Signal levels (max) | response (Hz) | |
| 10 | MIC input |
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Microphone | 9 | MIC voltage reference | 1Vrms | 20 – 20k | |
7 | output | ||||
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| Audio ground reference. |
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| 1 | Line input left |
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Line in | 5 | Line input right | 1Vrms | 20 – 20k | |
| 3 | Audio ground reference |
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| 2 | Line output left |
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Line out | 6 | Line output right | 1Vrms | 20 – 20k | |
| 4 | Audio ground reference |
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| 8 | Amp output left | 1.79V peak |
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Amp out | 11 | Amp output right | 1.26Vrms | 20 – 20k | |
| 12 | Audio ground reference | (8Ω load) 223mW |
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© 2007 Eurotech Ltd Issue D | 49 |