AD1984 Analog Devices, Inc., AD1984 Datasheet - Page 12

• Manufacturer Part Number: AD1984
• Description: High Definition Audio Soundmax Codec
• Manufacturer: Analog Devices, Inc.

AD1984
DIGITAL MICROPHONE INTERFACE TIMING SPECIFICATIONS
The digital microphone interface can support one, two, or four
digital microphones using two or three codec pins. Both uniplex
(one mic per data pin) and multiplex (two mics sharing the
same data pin) are supported. These configurations are shown
Table 4. Digital Microphone Timing Parameters
Parameter
Timing Requirements
t
t
t
t
t
t
t
t
t
0
0
0
1
2
3
4
5
6
MIC 1
DM_CLK (1.5 MHz) Period
DM_CLK (2.0 MHz) Period
DM_CLK (3.0 MHz) Period
DM_CLK Rise Time
DM_CLK Fall Time
DM_CLK Edge to Data Valid
Data Setup to DM_CLK Edge
Data Hold from DM_CLK Edge
DM_CLK Edge to Data Hi-Z
OFF -CHIP
DM_CLK
DM_3/4
DM_1/2
Duty Cycle
Duty Cycle
Duty Cycle
ON CHIP
SWAP L/R
Figure 3. Uniplex Digital Microphone, Mono Interface
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Rev. 0 | Page 12 of 20 | January 2007
Q
Q
Q
Q
GENERATOR
DM-CLK
MUX
in
generate a microphone clock at 1.5 MHz, 2.0 MHz, or 3.0 MHz
to suit quality and power requirements.
Figure
Min
100
5
GAM = GAIN, ATTENUATE, MUTE
3,
GAM
GAM
GAM
GAM
Figure
4,
Figure
Typ
667
60/40
500
50/50
333
50/50
40
7
D IGITAL FILTER
DIGITAL F ILTER
NID:06
NID:05
6, and
Figure
Max
5
5
RIGHT
RIGHT
LEFT
LEFT
7. The interface can
Unit
ns
%
ns
%
ns
%
ns
ns
ns
ns
ns
ns