wm8961 Wolfson Microelectronics plc, wm8961 Datasheet - Page 44

• Manufacturer Part Number: wm8961
• Description: Ultra-low Power Stereo Codec With 1w Stereo Class D Speaker Drivers And Ground Referenced Headphone Drivers
• Manufacturer: Wolfson Microelectronics plc

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WM8961
Table 30 Headphone Output Enable Control
REGISTER
ADDRESS
R69 (45h)
Analogue
HP 0
BIT
7
6
5
4
3
2
1
0
Table 29 Headphone Output Drive Volume Control
HEADPHONE OUTPUT ENABLE
The staged enabling of the headphone outputs can be controlled using register R69. The HPL_ENA
and HPR_ENA enable the headphone amplifiers. The HPL_ENA_OUTP and HPR_ENA_OUTP
should be enabled following any offset cancellation by the DC Servo.
HEADPHONE OUTPUT CIRCUIT
It is recommended that the HP-L and HP_R is connected to a zobel network consisting of a 20 Ω
resistor (5% tolerance) and a 100nF capacitor (20% tolerance). This ensures the stability of the
headphone output amplifier. This is also illustrated in Figure 19.
R71 (47h)
Analogue HP 2
HPR_RMV_SHORT
HPL_RMV_SHORT
HPR_ENA_OUTP
HPL_ENA_OUTP
REGISTER
ADDRESS
HPR_ENA_DLY
HPL_ENA_DLY
HPR_ENA
HPL_ENA
LABEL
8:6
5:3
BIT
HPL_VOL[2:0]
HPR_VOL[2:0]
DEFAULT
LABEL
0
0
0
0
0
0
0
0
Left channel output short removal: set after output stage
has been enabled
Enables left channel output stage; set after offset
cancellation is done
delayed left channel enable, set with at least 20us delay
to HPL_ENA; reset together with HPL_ENA
Enables left headphone amplifier channel
right channel output short removal: set after output
stage has been enabled
enables right channel output stage; set after offset
cancellation is done
delayed right channel enable, set with at least 20us
delay to HPR_ENA; reset together with HPR_ENA
Enables right headphone amplifier channel
111
111
DEFAULT
Secondary HPL PGA Volume
111
110
101
100
011
010
001
000
Secondary HPR PGA Volume
111
110
101
100
011
010
001
000
DESCRIPTION
-3dB
-5dB
-7dB
-3dB
-5dB
-7dB
-1dB
-2dB
-4dB
-6dB
-1dB
-2dB
-4dB
-6dB
0dB (default)
0dB (default)
DESCRIPTION
PP, August 2009, Rev 3.1
Pre-Production
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