AK4695 Datasheet, PDF (29/107 Pages) Asahi Kasei Microsystems – 24bit 4ch CODEC with MIC/HP/SPK/LINE-AMP

[AK4695]
■ Digital MIC
1. Connection to Digital Microphones
The AK4695 can be connected to a digital microphone by setting DMIC bit = “1”. When DMIC bit is set to “1”, the
MICIN0L and MICIN1L pins become DDAT0 (digital microphone data input 0) and DMCLK (digital microphone clock
supply) pins respectively. The same voltage as AVDD must be provided to the digital microphone. The Figure 19 and
Figure 20 show mono/stereo connection examples. The DMCLK signal is output from the AK4695, and the digital
microphone outputs 1bit data, which is generated by a Modulator, from DMDAT. PMDM0/1/2/3 bits control power
up/down of the digital block (Decimation Filter and HPF). PMDM0/1/2/3 bits settings do not affect the digital microphone
power management. The DCLKE bit controls ON/OFF of the output clock from the DMCLK pin. When the AK4695 is
powered down (PDN pin= “L”), the DMCLK, DDAT0 and DDAT1 pins are floating state. Pull-down resistors must be
connected to the DMCLK, DDAT0 and DDAT1 pins externally to avoid this floating state.
AVDD
VDD
AMP



Modulator
Lch
VDD
AMP



Modulator
AK4695
DMCLK(64fs)
100k
DDAT0
R
DIV
PMDM0/1 bits
Decimation _HPF
Filter
Programmable
Filter
ALC
MCKI
SDTO1
Rch
Figure 19. Connection Example of Stereo Digital MIC
MS1463-E-01
- 29 -
2014/12