wm8594seft-v Wolfson Microelectronics plc, wm8594seft-v Datasheet - Page 35

• Manufacturer Part Number: wm8594seft-v
• Description: 24-bit 192khz 2vrms Multi-channel Codec
• Manufacturer: Wolfson Microelectronics plc

Production Data
ANALOGUE ROUTING CONTROL
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Figure 19 Analogue Routing Paths and Control
The WM8594 has a number of analogue paths, allowing flexible routing of a number of analogue
input signals and DAC output signals at levels up to 2Vrms. The analogue paths include volume
control with zero cross, optional soft ramp and soft mute, and flexible routing of analogue inputs and
DAC outputs to analogue outputs.
There are a total of ten (five stereo) analogue input channels and four (two stereo) DAC output
channels. Two of the ten input channels can be routed to the ADC. Any six of the 14 total channels
can be routed to the analogue outputs.
Figure 19 illustrates the various blocks of the analogue routing paths within the WM8594. The
following sections describe the control bits associated with the WM8594 analogue paths. Figure 19
also shows where these control bits take affect on the WM8594.
ANALOGUE VOLUME CONTROL
Each analogue bypass channel includes analogue volume control. Volume changes can be applied
to each channel immediately as they are written. Alternatively, all volume changes can be written,
and then all volume changes can be applied simultaneously using the volume update feature.
Volume control includes optional zero cross functionality. When zero cross is enabled, volume
changes are not applied until the output level crosses the DC level of the analogue channel (VMID).
Zero cross helps to prevent pop and click noise when changing volume settings.
The zero cross function includes a timeout which forces volume changes if a zero cross event does
not occur. The timeout period is a maximum of 278ms.
PD Rev 4.1 July 2008
WM8594
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