MAX9888 Maxim Integrated Products, MAX9888 Datasheet - Page 98

• Manufacturer Part Number: MAX9888
• Description: Stereo Audio CODEC
• Manufacturer: Maxim Integrated Products

DataSheet.in
Figure 31. Output Bypass Switch Block Diagrams
Table 30. Output Bypass Switches Register
Stereo Audio CODEC
with FLEXSOUND Technology
The IC includes two output bypass switches that solve
common applications problems. When a single trans-
ducer is used for the loudspeaker and receiver, the need
exists for two amplifiers to power the same transducer.
Bypass switches connect the IC’s receiver amplifier
output to the speaker amplifier’s output, allowing either
amplifier to power the same transducer. In systems where
98
*OPTIONAL 10I RESISTORS IMPROVE DISTORTION
THROUGH THE ANALOG SWITCH.
REGISTER
0x48
RECEN
SPLEN
0dB
+6dB
POWER/DISTORTION
SPEAKER AMPLIFIER BYPASS USING AN
RECBYP
LIMITER
SPKBYP
EXTERNAL RECEIVER AMPLIFIER
BIT
7
4
1
0
RECN/RXINN
RECP/RXINP
SPKLGND
SPKLVDD
SPKLN
SPKLP
MIC2BYP
RECBYP
Output Bypass Switches
SPKBYP
INABYP
NAME
10I*
10I*
EXTERNAL
RECEIVER
AMP
See the Microphone Inputs section.
RXINP to RXINN Bypass Switch
Shorts RXINP to RXINN allowing a signal to pass through the MAX9888. Disable the
receiver amplifier when RECBYP = 1.
0 = Disabled
1 = Enabled
RXIN to SPKL Bypass Switch
Shorts RXINP/RXINN to SPKLP/SPKLN allowing either the internal or an external
receiver amplifier to power the left speaker. Disable the left speaker amplifier when
SPKBYP = 1.
0 = Disabled
1 = Enabled
SPEAKER AMPLIFIER BYPASS USING THE
RECEN
SPLEN
0dB
+6dB
POWER/DISTORTION
INTERNAL RECEIVER AMPLIFIER
LIMITER
RECBYP
SPKBYP
RECN/RXINN
RECP/RXINP
SPKLGND
SPKLVDD
an external receiver amplifier is used, route its output to
the left speaker through RECP/RXINP and RECN/RXINN,
bypassing the Class D amplifier. In systems where an
external amplifier drives both the receiver and the IC’s
line input, one of the differential signals can be discon-
nected from the receiver when not needed by passing it
through the analog switch that connects RECP/RXINP to
RECN/RXINN.
SPKLN
SPKLP
DESCRIPTION
RECEN
SPLEN
0dB
+6dB
POWER/DISTORTION
LIMITER
RECBYP
CONTROLLING AN EXTERNAL RECEIVE
SPKBYP
AMPLIFIER AND SPEAKER
RECN/RXINN
RECN/RXINN
SPKLVDD
SPKLGND
SPKLP
SPKLN
RECEIVER AMP
EXTERNAL