AK4636 Datasheet, PDF (41/105 Pages) Asahi Kasei Microsystems – 16-Bit Mono CODEC with ALC & MIC/SPK/Video-AMP

[AK4636]
■ Digital MIC
1. Connection to Digital MIC
The AK4636 can be connected to digital microphone by setting DMIC bit = “1”. When DMIC bit is set to “1”, the MPI,
LIN and MIC pins become DMP (digital microphone power supply), DMCLK (digital microphone clock supply) and
DMDAT (digital microphone data input) pins respectively. By setting DMPE bit = “1”, the DMP (digital microphone
power supply) pin and can supply the power to the digital microphone (max. 2mA). When DMPE bit = “0”, the same
power supply as AVDD must be provided to the digital microphone. The Figure 39 and Figure 40 show connection
examples. The DMCLK signal is output from the AK4636, and the digital microphone outputs 1bit data, which is
generated by ΔΣModulator, from DMDAT. PMDML/R bits control power up/down of the digital block (Decimation
Filter and Digital Filter). PMADL/PMADR bits settings do not affect the digital microphone power management. The
DCLKE bit controls ON/OFF of the clock output from the DMCLK pin. When the AK4636 is powered down (PDN pin=
“L”), the DMCLK and DMDAT pin are floating state. Pull-down resistors must be connected to the DMCLK and
DMDAT pin externally to avoid floating state.
VDD
AMP
ΔΣ
Modulator
DMP
DMCLK(64fs)
100kΩ
DMDAT
R
AK4636
AVDD
DMPE = “1”
PLL
MCKI
Decimation _HPF1
Filter
P rogram mab le
Filter
ALC
SDTO
Figure 39. Connection Example of Digital MIC (DMPE bit = “1”)
AVDD
VDD
AMP
ΔΣ
Modulator
DMP
DMCLK(64fs)
100k Ω
DMDAT
R
AVDD ^AK4636
DMPE = “0”
PLL
MCKI
Decimation _HPF1
Filter
P rogram mab le
Filter
ALC
SDTO
Figure 40. Connection Example of Digital MIC (DMPE bit = “0”)
MS1012-E-01
- 41 -
2010/08