WM9715L
Production Data
ANALOGUE AUDIO OUTPUTS
The following sections give an overview of the analogue audio output pins. For more information on
recommended external components, please refer to the “Applications Information” section.
HEADPHONE OUTPUTS – HPOUTL AND HPOUTR
The HPOUTL and HPOUTR (pins 39 and 41) are designed to drive a 16Ω or 32Ω headphone or a
line output. They can also be used as line-out pins. The output signal is produced by the headphone
mixer.
The signal volume on HPOUTL and HPOUTR can be independently adjusted under software control
by writing to register 04h. When HPOUTL and HPOUTR are not used, the output drivers can be
disabled to save power (see “Power Management” section). Both pins remain at the same DC level
(the reference voltage VREF) when they are disabled, so that no click noise is produced.
REGISTER
ADDRESS
BIT
LABEL
MUTE
DEFAULT
DESCRIPTION
04h
15
1
Mute HPOUTL and HPOUTR
1: Mute (OFF)
HPOUTL /
HPOUTR
0: No Mute (ON)
Volume
13:8
HPOUTLVOL
000000
(0dB)
HPOUTL Volume
000000: 0dB (maximum)
000001: -1.5dB
… (1.5dB steps)
011111: -46.5dB
1xxxxx: -46.5dB
7
ZC
0
Zero Cross Enable
0: Change gain immediately
1: Change gain only on zero crossings,
or after time-out
5:0
HPOUTRVOL
00000
(0dB)
HPOUTR Volume
Similar to HPOUTLVOL
Table 15 HPOUTL / HPOUTR Control
PD Rev 4.0 December 2007
30
w
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
