WM8776SEFT/V Wolfson Microelectronics, WM8776SEFT/V Datasheet - Page 32

• Manufacturer Part Number: WM8776SEFT/V
• Description: Audio CODECs Stereo CODEC with 5-Ch Mux
• Manufacturer: Wolfson Microelectronics

Specifications of WM8776SEFT/V

• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: TQFP-48
• Minimum Operating Temperature: - 25 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

WM8776
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Table 14 Digital Volume Control Attenuation Levels
The digital volume control also incorporates a zero cross detect circuit which detects a transition
through the zero point before updating the digital volume control with the new volume. This is
enabled by control bit DZCEN.
DAC OUTPUT PHASE
The DAC Phase control word determines whether the output of the DAC is non-inverted or inverted
ADC GAIN CONTROL
The ADC has an analogue input PGA and digital gain control for each stereo channel. Both the
analogue and digital gains are adjusted by the same register, LAG for the left and RAG for the right.
The analogue PGA has a range of +24dB to -21dB in 0.5dB steps. The digital gain control allows
further attenuation (after the ADC) from -21.5dB to -103dB in 0.5dB steps. Table 15 shows how the
register maps the analogue and digital gains.
Table 15 Analogue and Digital Gain Mapping for ADC
In addition, a zero cross detect circuit is provided for the input PGA, controlled by bit 8 in each
attenuation register. This minimises audible clicks and ‘zipper’ noise by updating the gain when the
signal crosses the zero level.
REGISTER ADDRESS
REGISTER ADDRESS
LAG/RAG[7:0]
CF(hex)
FE(hex)
A4(hex)
A5(hex)
FF(hex)
00(hex)
01(hex)
DAC Control
DAC Phase
L/RDA[7:0]
R7 (07h)
0000111
R6 (06h)
0000110
FE(hex)
FF(hex)
:
:
:
00(hex)
01(hex)
:
:
:
ATTENUATION
-∞ dB (mute)
BIT
BIT
1:0
LEVEL (AT
0
OUTPUT)
+23.5dB
-21.5dB
-103dB
+24dB
-21dB
0dB
ATTENUATION LEVEL
:
:
:
DZCEN
LABEL
LABEL
PH[1:0]
-∞ dB (mute)
-127dB
-0.5dB
0dB
:
:
:
DEFAULT
DEFAULT
ANALOGUE PGA
00
0
+23.5dB
+24dB
-21dB
-21dB
-21dB
-21dB
0dB
:
:
:
DAC Digital Volume Zero Cross
Enable:
Bit
0
1
0: Zero cross detect disabled
1: Zero cross detect enabled
PD, Rev 4.1, September 2008
DESCRIPTION
DESCRIPTION
DAC
DACL
DACR
ATTENUATION
Digital mute
DIGITAL
-0.5dB
-82dB
0dB
0dB
0dB
0dB
:
:
:
Production Data
Phase
1 = invert
1 = invert
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