wm9714l Wolfson Microelectronics plc, wm9714l Datasheet - Page 56

• Manufacturer Part Number: wm9714l
• Description: Ac?97 Audio Codec
• Manufacturer: Wolfson Microelectronics plc

WM9714L
SPEAKER OUTPUTS – SPKL AND SPKR
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Table 35 Mono PGA Control
The SPKL and SPKR (pins 35 and 36) are designed to drive a loudspeaker load down to 8Ω and can
also be used as line outputs and headphone outputs. They are designed to drive an 8Ω load AC
coupled or in a BTL (capless) configuration. The available input sources are HPMIXL/R, SPKMIXL/R,
INV1/2 and Vmid (see Table 36).
Table 36 SPKL / SPKR PGA Input Source
The signal volume on SPKL and SPKR can be independently adjusted under software control by
writing to register 02h.
When not in use SPKL and SPKR can be powered down using the Powerdown register bits SPKL
and SPKR (register 3Eh, bits [8:7]). To minimise pops and clicks when the PGA is powered down /
up it is recommended that the Vmid input is selected during the power down / up cycle. This ensures
the same DC level is maintained on the output pin throughout.
08h
MONO Vol
1Ch
Output PGA
Mux Select
REGISTER
REGISTER
ADDRESS
ADDRESS
7
6
5:0
13:11
10:8
BIT
BIT
MU
ZC
MONOVOL
SPKL
SPKR
LABEL
LABEL
1 (Mute)
0
000000
(0dB)
000
(Vmid)
000
(Vmid)
DEFAULT
DEFAULT
MONO Mute Control
1 = Mute
0 = No mute
MONO Zero Cross Control
1 = Zero cross enabled (change volume
only on zero crossings, or after time-out)
0 = Zero cross disabled (change volume
immediately)
MONO Volume Control
000000 = 0dB (maximum)
… (1.5dB steps)
011111 = -46.5dB
1xxxxx = -46.5dB
SPKL Source Control
000 = VMID
001 = No input (tri-stated if SPKL is
disabled in 3Eh)
010 = HPMIXL
011 = SPKMIX
100 = INV1
All other values are reserved
SPKR Source Control
000 = VMID
001 = No input (tri-stated if SPKR is
disabled in 3Eh)
010 = HPMIXR
011 = SPKMIX
100 = INV2
All other values are reserved
DESCRIPTION
DESCRIPTION
PP, Rev 3.2, October 2008
Pre-Production
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