AK5701_07 Datasheet, PDF (25/64 Pages) Asahi Kasei Microsystems – 16-Bit ΔΣ Stereo ADC with PLL & MIC-AMP

[AK5701]
■ PLL Slave Mode (PMPLL bit = “1”, M/S bit = “0”)
A reference clock of PLL is selected among the input clocks to the MCKI, EXBCLK or EXLRCK pin. The required clock
to the AK5701 is generated by an internal PLL circuit. Input frequency is selected by PLL3-0 bits (Table 4).
a) PLL reference clock: MCKI pin
EXBCLK and EXLRCK inputs should be synchronized with MCKO output. The phase between MCKO and EXLRCK is
not important. The MCKO pin outputs the frequency selected by PS1-0 bits (Table 9) and the output is enabled by MCKO
bit. Sampling frequency can be selected by FS3-0 bits (Table 5).
AK5701
11.2896MHz, 12MHz, 12.288MHz, 13MHz
13.5MHz, 19.2MHz, 24MHz, 26MHz, 27MHz
DSP or μP
MCKI
MCKO
EXBCLK
EXLRCK
256fs/128fs/64fs/32fs
≥ 32fs
1fs
MCLK
BCLK
LRCK
SDTO
SDTI
Figure 20. PLL Slave Mode 1 (PLL Reference Clock: MCKI pin)
The external clocks (MCKI, EXBCLK and EXLRCK) should always be present whenever the ADC is in operation
(PMADL bit = “1” or PMADR bit = “1”). If these clocks are not provided, the AK5701 may draw excess current and it is
not possible to operate properly because utilizes dynamic refreshed logic internally. If the external clocks are not present,
the ADC should be in the power-down mode (PMADL=PMADR bits = “0”).
b) PLL reference clock: EXBCLK or EXLRCK pin
Sampling frequency corresponds to 7.35kHz to 48kHz by changing FS3-0 bits (Table 6).
AK5701
MCKI
EXBCLK
EXLRCK
SDTO
DSP or μP
32fs, 64fs
1fs
BCLK
LRCK
SDTI
Figure 21. PLL Slave Mode 2 (PLL Reference Clock: EXLRCK or EXBCLK pin)
MS0404-E-02
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2007/08