WM8903LGEFK/V Wolfson Microelectronics, WM8903LGEFK/V Datasheet - Page 85

• Manufacturer Part Number: WM8903LGEFK/V
• Description: Audio CODECs ULTRA LOW PWR HI FI CODEC
• Manufacturer: Wolfson Microelectronics

Specifications of WM8903LGEFK/V

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Pre-Production
w
Companding uses a piecewise linear approximation of the following equations (as set out by ITU-T
G.711 standard) for data compression:
μ-law (where μ=255 for the U.S. and Japan):
A-law (where A=87.6 for Europe):
Figure 52 μ-Law Companding
Figure 53 A-Law Companding
F(x) = A|x| / ( 1 + lnA)
F(x) = ( 1 + lnA|x|) / (1 + lnA)
120
100
120
100
80
60
40
20
F(x) = ln( 1 + μ|x|) / ln( 1 + μ)
80
60
40
20
0
0
0
0
0.1
0.2
0.2
0.3
u-law Companding
A-law Companding
0.4
Normalised Input
0.4
Normalised Input
} for -1 ≤ x ≤ 1
} for x ≤ 1/A
} for 1/A ≤ x ≤ 1
0.5
0.6
0.6
0.7
0.8
0.8
PP, Rev 3.1, August 2009
0.9
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
WM8903
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