Datasheet

Maxim Integrated │ 86
MAX98090 Ultra-Low Power Stereo Audio Codec
www.maximintegrated.com
Analog Microphone Inputs
The device includes three differential microphone inputs
(three for the WLP package and two for the TQFN pack-
age) and a programmable, low-noise microphone bias
for powering a wide variety of external micro phones
(Figure 6). By default, analog inputs IN1 and IN2 differen-
tially (IN1/IN2) provide the input to microphone amplifier
1, while IN3 and IN4 differentially (IN3/IN4) form the input
to microphone amplifier 2. For the WLP package, the
additional analog input pair (IN5 and IN6) can be con-
figured as a differential input (IN5 - IN6) to either micro-
phone amplifier 1 or 2 (Table 24).
In the typical application, one microphone input is used
for the handset microphone and the other is used as an
accessory microphone (IN1/IN2 and IN3/IN4). In systems
using a background noise microphone, IN5/IN6 (WLP
only) can be retasked as another microphone input.
Figure 6. Analog Microphone Input Functional Diagram
MBEN
PA1EN[1:0] EXTMIC[0]
MBVSEL[1:0]
MIC 1
INPUT
MUX
MICBIAS
MICROPHONE
BIAS
GENERATOR
MIC 1
PREAMP
PGAM1[4:0]
0dB TO 20dB
0dB TO 20dB
0dB
10dB
30dB
0dB
10dB
30dB
IN1-IN2
IN3-IN4
IN5-IN6
MIC 1
MIC 2
LINE A
LINE B
IN1-IN2
IN3-IN4
IN5-IN6
MIC 1
MIC 2
LINE A
LINE B
MIC 1
PGA
MIC 2
INPUT
MUX
MIC 2
PREAMP
ZDENB
PA2EN[1:0] EXTMIC[1] PGAM2[4:0]
ADC
LEFT
MIXER
ADC
RIGHT
MIXER
MIC 2
PGA
IN1-IN2
IN5-IN6
LINE A
LINE B
IN1/DMD
IN2/DMC
IN5
IN3-IN4
IN5-IN6
ANALOG
OUTPUT
MIXERS
MAX98090
MIXADR[6:0]
MIXADL[6:0]
IN6
(WLP ONLY)
IN3
IN4