Production Data
WM8501
POWER UP/DOWN SEQUENCE
POWER UP/DOWN SEQUENCE
For click free operation, the WM8501 should be powered up and down in a specific sequence.
Power-up:
1. Power up AVDD and DVDD and wait to settle
2. Turn on clocks and data (MCLK, BCLK, LRCLK, SDATA)
3. Switch ENABLE pin from low to high
Power-down:
1. Switch Enable from high to low
2. Remove clocks and data
3. Power down AVDD and DVDD
RECOMMENDED ANALOGUE LOW PASS FILTER
Ω
Ω
Ω
Ω
Figure 18 Recommended 1st Order Low Pass Filter
Note: Capacitors should be COG dielectric.
An external single pole RC filter is recommended (see Figure 18) if the device is driving a
wideband amplifier. However the WM8501 does contain an internal low pass filter which should
be adequate in most applications.
PD, Rev 4.2, July 2009
17
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
