wm8961 Wolfson Microelectronics plc, wm8961 Datasheet - Page 45

• 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
Figure 19 Recommended Headphone Output Configuration
HEADPHONE OUTPUT BIAS BOOST
In order to increase the signal to noise ratio (SNR) of the headphone output, the HP_PGAS_BIAS[2:0]
and HP_BIAS_BOOST[2:0] register bits can be used to increase the bias current to the headphone
output drive as shown in Table 31. There will be a slight increase in power consumption when a bias
boost greater than x1 is selected.
Table 31 Headphone Output Bias Boost
R68 (44h)
Analogue PGA
Bias
R71 (47h)
Analogue HP 2
REGISTER
ADDRESS
2:0
2:0
BIT
HP_PGAS_BIA
S[2:0]
HP_BIAS_BOO
ST[2:0]
LABEL
011
011
DEFAULT
Headphone PGA bias options
000
001
010
011
100-111 Reserved
Boost bias into headphone driver
000:
001:
010:
011:
100-111 Reserved
x2
Reserved
Reserved
x1
x 2
Reserved
Reserved
x 1
DESCRIPTION
PP, August 2009, Rev 3.1
Pre-Production
45