AK4950 Datasheet, PDF (92/106 Pages) Asahi Kasei Microsystems – 24bit Stereo CODEC with MIC/SPK/Cap-less VIDEO-AMP & mini DSP

[AK4950]
CONTROL SEQUENCE
■ Clock Set up
When ADC, DAC, Digital Microphone and Programmable Filter are used, the clocks must be supplied.
1. PLL Master Mode
Power Supply
PDN pin
MCKO bit
(Addr:01H, D17)
PLL3-0 bits
(Addr:07H, D20-23)
FS3-0 bits
(Addr:08H, D19-16)
PMPLL bit
(Addr:01H, D16)
MCKI pin
M/S bit
(Addr:01H, D3)
BICK pin
LRCK pin
MCKO pin
INIT bit
(Addr:0EH, D16)
(1)
1msec(min)
(3)
(2)
(4)
Default
(5)
Default
(6)
"1100"
"1011"
Example:
Audio I/F Format: MSB justified (ADC & DAC)
BICK frequency at Master Mode: 64fs
Input Master Clock Select at PLL Mode: 13.5MHz
MCKO: Enable
Sampling Frequency: 48kHz
(1) Power Supply & PDN pin = “L” Æ “H”
Input
10msec(max)
10msec(max)
(8)
10msec(max)
(7)
Output
(9)
Output
(10)
(2) Wait time (min)1ms
(3) Addr:01H, Data:0AH
(4) Addr:07H, Data:C2H
(5) Addr:08H, Data:0BH
(6) Addr:01H, Data:0BH
MCKO, BICK and LRCK output
Figure 66. Clock Set Up Sequence (1)
<Example>
(1) After Power Up, PDN pin = “L” → “H”
“L” time (1) of 150ns or more is needed to reset the AK4950.
(2) PDN pin reset release waiting time
Wait time of 1ms or more is needed for the internal VCOM voltage rising.
(3) In case of using MCKO output: MCKO bit = “1”
In case of not using MCKO output: MCKO bit = “0”
(4) PLL mode setting. (When the reference clock is MCKI = 13.5MHz, PLL3-0 bits = “1100”)
(5) Sampling frequency setting. (In case of fs = 48kHz, FS3-0 bits = “1011”)
(6) PLL lock time is 10ms (max) after PMPLL bit changes from “0” to “1” and MCKI is supplied from an external
source.
(7) The AK4950 starts outputting the LRCK and BICK clocks after the PLL becomes stable and the normal
operation starts.
(8) Invalid clock is output from MCKO pin during this period when MCKO bit = “1”.
(9) Normal clock is output from the MCKO pin after PLL is locked when MCKO bit = “1”.
(10) Digital Function Initializing
Digital functions can be initialized by setting INIT bit = “0” → “1” after normal clock is output from the
MCKO pin. The initializing time is 1/512fs x 18,000 [s]. INIT bit returns to “0” automatically when the
initialization is finished. This initialization must be executed when using ALC and Programmable Filter.
MS1320-E-00
- 92 -
2011/10