wm8961 Wolfson Microelectronics plc, wm8961 Datasheet - Page 76

• Manufacturer Part Number: wm8961
• Description: Ultra-low Power Stereo Codec With 1w Stereo Class D Speaker Drivers And Ground Referenced Headphone Drivers
• Manufacturer: Wolfson Microelectronics plc

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WM8961
Table 57 ADC and DAC Maximum Word Lengths Based on Valid BCLK (master mode) Configuration
SYSCLK
11.2896
12.288
(MHz)
fs=48 kHz
Fs=32 kHz
fs=44.1 kHz
Fs=22.05
kHz
SAMPLE
RATE
0x100
=BCLK/256 = 48 kHz
0x040
= BCLK/64 = 48 kHz
0x180
=BCLK/384 = 32 kHz
0x040
= BCLK/64 = 32 kHz
0x020
= BCLK/32 = 32 kHz
0x100
=BCLK/256 = 44.1
kHz
0x040
= BCLK/64 = 44.1
kHz
0x080
=BCLK/128 = 22.05
kHz
MASTER MODE BCLK CONFIGURATION
The ADC and DAC must be configured to operate at the same sample rate. In master mode the BCLK
and LRCLK_RATE must be configured to support this sample rate. The following Table 57 shows
example calculations of the maximum word length supported for the ADC and DAC running at
different sample rates. Note that ADCDIV, DACDIV and LRCLK_RATE must be configured to be the
same sample rate.
LRCLKRATE
0000 (=1)
0100 (=4)
0000 (=1)
0110 (=6)
1001 (=12)
0000 (=1)
0100 (=4)
0100 (=4)
BCLKDIV
12.288
3.072
12.288
2.048
1.024
11.2896
2.8224
2.8224
(MASTER MODE)
BCLK RATE
(MHz)
(12.288 MHz/48 kHz) / 2
= 128.
=> 32 bit word length supported.
(3.072 MHz/48 kHz) / 2
= 32.
=> 32 bit word length supported.
(12.288 MHz/32 kHz) / 2
= 192.
=> 32 bit word length supported.
(2.048 MHz/32 kHz) / 2
= 32.
=> 32 bit word length supported.
(1.024 MHz/32 kHz) / 2
=> 16 bit word length supported.
(11.2896MHz/44.1 kHz) / 2
= 128.
=> 32 bit word length supported.
(2.8224MHz/44.1 kHz) / 2
= 32.
=> 32 bit word length supported.
(2.8224MHz/22.05 kHz) / 2
= 64.
=> 32 bit word length supported.
= 16.
MAXIMUM WORD LENGTH (AT
ADC/DAC SAMPLE RATE)
PP, August 2009, Rev 3.1
Pre-Production
76