WM8900LGEFK/RV Wolfson Microelectronics, WM8900LGEFK/RV Datasheet - Page 19

• Manufacturer Part Number: WM8900LGEFK/RV
• Description: Audio CODECs Ultra Low Power Hi-Fi CODEC
• Manufacturer: Wolfson Microelectronics

Specifications of WM8900LGEFK/RV

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

Production Data
Table 7 External Components for WM8900
Please refer to WAN0188 for further details on the selection of external components for WM8900
RECOMMENDED TEST METHOD FOR TESTING AUDIO OUTPUTS
w
IDENTIFIER
C10
C11
C12
C13
C14
C15
C16
C17
C18
C19
C20
C21
C22
R10
C1
C2
C3
C4
C5
C6
C7
C8
C9
R1
R2
R3
R4
R9
0.47 uF
0.47 uF
VALUE
2.2 kΩ
2.2 kΩ
49.9 Ω
49.9 Ω
0.1 uF
0.1 uF
4.7 uF
4.7 uF
4.7 uF
4.7 uF
4.7 uF
10 uF
10 uF
22 nF
22 nF
Most modern lab test equipment contains high speed A-D converter circuits hence can be sensitive
to frequencies outside of the audio band which appear at their inputs. The software or hardware
filters included in such test equipment may not be sufficient to attenuate out of band frequencies
from the WM8900 charge pump. Although this does not affect performance within the audio band,
false triggering of the test equipment outside the audio band can give inaccurate results. An
external filter with a very steep attenuation curve above the audio band is recommended, such as
the AUX0025 from Audio Precision (http://www.ap.com), or any filter which has a similar frequency
response.
The connection method is shown in Figure 2. The 100k resistance at each channel of the Audio
Analyzer Input represents the Analyser’s input impedance. These resistors are not required as
additional components during measurement.
1 uF
1 uF
1 uF
1 uF
1 uF
1 uF
1 uF
1 uF
1 uF
0 Ω
0 Ω
DBVDD decoupling
DCVDD decoupling
AVDD decoupling
CPVDDLO decoupling
CPVDDHI decoupling
LINPUT2 DC blocking
LINPUT1 DC blocking
VMID decoupling
MICBIAS decoupling
RINPUT2 DC blocking
RINPUT1 DC blocking
LINPUT3 DC blocking
RINPUT3 DC blocking
HP_INL DC blocking
HP_INR DC blocking
Charge Pump capacitor
VNEG decoupling
VPOS decoupling
Headphone zobel network
Headphone zobel network
LINEOUT_L DC blocking
LINEOUT_R DC blocking
LINPUT2 Bias Current limit
RINPUT2 Bias Current limit
LINPUT1 Ground
RINPUT1 Ground
Headphone zobel network
Headphone zobel network
FUNCTION
All applications
Ground Referenced Headphone Amplifier
Left Microphone Input
All applications
Right Microphone Input
Left Line Input
Right Line Input
Ground Referenced Headphone Amplifier
Headphone Amp
Left Line Output
Right Line Output
Left Microphone Input
Right Microphone Input
Left Microphone Input
Right Microphone Input
Headphone Amp in Normal mode
REQUIRED FOR
PD, August 2008, Rev 4.0
WM8900
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