92hd81 Integrated Device Technology, 92hd81 Datasheet - Page 32

• Manufacturer Part Number: 92hd81
• Description: Single Chip Pc Audio System
• Manufacturer: Integrated Device Technology

SINGLE CHIP PC AUDIO SYSTEM, CODEC+SPEAKER AMPLIFIER+CAPLESS HP+LDO
92HD81
SINGLE CHIP PC AUDIO SYSTEM, CODEC+SPEAKER AMPLIFIER+CAPLESS HP+LDO
2.18. BTL Amplifier
Headphone
SD/Mute
Internal
Amp
CODEC
An integrated class-AB stereo BTL amplifier is provided to directly drive 4 ohm speakers (2W @
4.75V) or 8 ohm speakers (1W @ 4.75V). No external filter is needed for cable runs of 18” or less.
An internal DC blocking filter prevents distortion when the audio source has DC content, and pre-
vents unintentional power consumption when pausing audio playback. The amplifier may be con-
trolled using the EAPD pin (see EAPD section.)
Figure 8. HP EAPD Example to be replaced by single pin for internal amp
Internal BTL
EAPD PIN
SD/Mute
Control
Amp
(MUTE LED ON
SAME BOARD)
UP/DOWN
BUTTONS
MUTE +
EAPD
HP AUDIO CONTROL BLOCK DIAGRAM
SCAN
CODES
SYNC FROM KBC TO OS
SMU MUTE
KBC
VDD
32
SYNC FROM AUDIO GUI TO KBC
A_EAPD
A_SD
SPKR_EN#
GPIO_1
SPKR AMP
OTHER
CODEC
OS
92HD81
SD#
Power Amp
External
PC AUDIO
V 0.97 01/09