max98088 Maxim Integrated Products, Inc., max98088 Datasheet - Page 104

• Manufacturer Part Number: max98088
• Description: Stereo Audio Codec With Flexsound Technology
• Manufacturer: Maxim Integrated Products, Inc.

Stereo Audio Codec
with FLEXSOUND Technology
Figure 30. Headphone Amplifier Block Diagram
104
Figure 28. Traditional Amplifier Output vs. DirectDrive Output
DirectDrive AMPLIFIER BIASING SCHEME
CONVENTIONAL AMPLIFIER BIASING SCHEME
DALEN
DAREN
DACL
DACR
GND
+V
GND
V
V
-V
(V
DD
DD
DD
SS
DD
MIXHPL
MIXHPR
/2
)
MIX
MIX
A Class H amplifier uses a Class AB output stage with
power supplies that are modulated by the output signal.
In the case of the ICs, two nominal power-supply differ-
entials of 1.8V (+0.9V to -0.9V) and 3.6V (+1.8V to -1.8V)
are available from the charge pump. Figure 29 shows the
operation of the output-voltage-dependent power supply
Figure 29. Class H Operation
MIXHPL_
PATH SEL
MIXHPR_
PATH SEL
V
V
-0.9V
-1.8V
TH_H
TH_L
1.8V
0.9V
HPVDD
HPVSS
HPLEN
HPREN
HPVOLL:
+3dB TO -67dB
HPVOLR:
+3dB TO -67dB
HPSNS
HPR
HPL
TBD
TBD
Class H Operation
OUTPUT
VOLTAGE