wm9707scft-v Wolfson Microelectronics plc, wm9707scft-v Datasheet - Page 33

• Manufacturer Part Number: wm9707scft-v
• Description: Ac?97 Revision 2.1 Audio Codec With Spdif Output
• Manufacturer: Wolfson Microelectronics plc

WM9707
RECOMMENDED EXTERNAL COMPONENTS VALUES
Table 18 External Component Values
Figure 19 Suggested SPDIF Output Circuit (DVDD = 5V)
RECOMMENDATIONS FOR 3.3V OPERATION
w
C1 to C4
C5 to C17
C18
C19
C20
C21
C22
C23
C24
C25 to C29
C30 and C31
R1
XT
COMPONENT
REFERENCE
470nF
100nF
1μF
0.1μF
10μF
0.1μF
10μF
100nF
47nF
10μF
22pF
1kΩ
24.576 MHz
SUGGESTED
VALUE
The device’s performance with AVDD = 3.3V is shown in Electrical Characteristics.
In 3.3V analogue operation, mid-rail reference scales to 1.65V. All ADC and DAC references are
2/3
660mVrms in 3.3V applications. It is not possible to produce an undistorted 1Vrms output by using
the mixer PGA gain whilst running from a 3.3V analogue supply.
rds
of their nominal 5V value. Input and output signals that are 1Vrms in 5V applications, scale to
DESCRIPTION
De-coupling for DVDD and AVDD
AC coupling capacitors for setting DC level of analogue inputs to VCAP1.
Ceramic type or similar.
3D high pass filter. This value sets nominal 1kHz.
Optional capacitors for better crystal frequency stability.
AC’97 master clock frequency. A bias resistor is not required, but if connected will not
Value chosen to give corner frequency below 20Hz for min 10K input impedance.
Reference de-coupling capacitors for ADC, DAC, Mixer and CAP2 references.
3D low pass filter. This value sets nominal 100Hz.
Output AC coupling caps to remove VREF DC level from outputs.
See note 3 above
affect operation if value is large (above 1MΩ).
PD, Rev 4.4, March 2009
Production Data
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