WM8976 Wolfson Microelectronics Ltd., WM8976 Datasheet - Page 72

• Manufacturer Part Number: WM8976
• Description: The WM8976 is a low power, high quality stereo codec designed for portable applications such as Digital still camera or Digital Camcorde
• Manufacturer: Wolfson Microelectronics Ltd.

WM8976
GENERAL PURPOSE INPUT/OUTPUT
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Figure 34 u-Law Companding
Figure 35 A-Law Companding
The WM8976 has two dual purpose input/output pins.
The GPIO2 function is provided for use as a jack detection input.
The GPIO1 function is provided for use as a jack detection input or a general purpose output.
The default configuration for the CSB/GPIO1 pin is to be an input.
When setup as an input, the CSB/GPIO1 pin can either be used as CSB or for jack detection,
depending on how the MODE pin is set.
Table 49 illustrates the functionality of the GPIO1 pin when used as a general purpose output.
120
100
120
100
80
60
40
20
80
60
40
20
0
0
CSB/GPIO1: CSB / GPIO pin
L2/GPIO2: Line input / headphone detection input
0
0
0.1
0.2
0.2
0.3
u-law Companding
A-law Companding
0.4
Normalised Input
0.4
Normalised Input
0.5
0.6
0.6
0.7
0.8
0.8
0.9
PP Rev 3.0 April 2006
1
1
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
Pre-Production
72