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Required June 1, 2006 Required June 1, 2007
    Audio Audio Audio Sysfund Sysfund Sysfund    
    0006 0006 0025 0118 0118 0127    
    Premium Mobile Basic Premium Mobile Basic    
Requirement Value Units Frequency range 
Analog Line Output Jack      
THD+N <= -80 -65 -65 -80 -65 -65 dBFS [20 Hz, 20 KHz] 
Dynamic range with signal present >= 90 80 80 90 80 80 dBFS A-weighted [20 Hz, 20 KHz] 
Magnitude Response <=+- 0.25 0.25 0.25 0.25 0.25 0.25 dB ripple (deviation from center) [20 Hz, 20 KHz] (5)
    Upper band edge limit < 1 1 1 1 1 1 dB [20 Hz, 20 KHz] (5)
    Lower band edge limit < 3 3 3 3 3 3 dB [20 Hz, 20 KHz] (5)
Sampling frequency accuracy < 0.02 0.02 0.02 0.02 0.02 0.02 %  
Line output cross-talk >= 60 50 50 60 50 50 dB [20 Hz, 15KHz] 
Full scale output voltage >= 1.000 0.707 1.000 1.000 0.707 1.000 Vrms  
Noise level during system activity <= -90 -80 -80 -90 -80 -80 dBFS A-weighted  
Interchannel phase delay < 30 30 30 30 30 30 degrees [20 Hz, 20 KHz] 
  < 12.5 12.5 12.5 12.5 12.5 12.5 microseconds [20 Hz, 20 KHz] 
Analog Speaker Output Jack (Example: 125mW into 8 Ohm load)          
THD+N <= -75 -65 -65 -75 -65 -65 dBFS [20 Hz, 20 KHz] 
Dynamic range with signal present >= 90 80 80 90 80 80 dBFS A-weighted [20 Hz, 20 KHz] 
Magnitude Response <=+- 0.25 0.25 0.25 0.25 0.25 0.25 dB ripple (deviation from center) [20 Hz, 20 KHz] (5)
    Upper band edge limit < 1 1 1 1 1 1 dB [20 Hz, 20 KHz] (5)
    Lower band edge limit < 3 3 3 3 3 3 dB [20 Hz, 20 KHz] (5)
Sampling frequency accuracy < 0.02 0.02 0.02 0.02 0.02 0.02 %  
Line output cross-talk >= 60 50 50 60 50 50 dB [20 Hz, 15 KHz] 
Full scale output voltage >= 1.000 0.707 1.000 1.000 0.707 1.000 Vrms  
Noise level during system activity <= -90 -80 -80 -90 -80 -80 dBFS A-weighted  
Interchannel phase delay < 30 30 30 30 30 30 degrees [20 Hz, 20 KHz] 
  < 12.5 12.5 12.5 12.5 12.5 12.5 microseconds [20 Hz, 20 KHz] 
Analog Headphone Out Jack                  
THD+N <= -75 -65 -65 -75 -65 -65 dBFS at 10k Ohm load [100 Hz, 20 KHz] 
  <= -55 -45 -45 -55 -45 -45 dBFS at 32 Ohm Load  
Dynamic range with signal present >= 87 80 80 87 80 80 dBFS A-weighted at 10k Ohm load [100 Hz, 20 KHz] 
  >= 67 60 60 67 60 60 dBFS A-weighted at 32 Ohm Load  
Magnitude Response <=+- 0.25 0.25 0.25 0.25 0.25 0.25 dB ripple (deviation from center) [100 Hz ,20 KHz] (5)
    Upper band edge limit < 1 1 1 1 1 1 dB [100 Hz ,20 KHz] (5)
    Lower band edge limit < 3 3 3 3 3 3 dB [100 Hz ,20 KHz] (5)
Sampling frequency accuracy < 0.02 0.02 0.02 0.02 0.02 0.02 %  
Headphone output cross-talk >= 60 50 50 60 50 50 dB [20 Hz, 15 KHz] 
  >= 60 50 50 50 50 50 dB for Front Panel HP at 32-ohm Load [20 Hz, 15 KHz] 
Full scale output voltage >= 1.000 0.707 1.000 1.000 0.707 1.000 Vrms at 320 Ohm load  
  >= 300 300 300 300 300 300 mVrms at 32 Ohm load (6)
Noise level during system activity <= -87 -80 -80 -87 -80 -80 dBFS A-weighted  
Interchannel phase delay < 30 30 30 30 30 30 degrees [20 Hz, 20 KHz] 
  < 12.5 12.5 12.5 12.5 12.5 12.5 microseconds [20 Hz, 20 KHz] 
Analog Line In Jack                  
THD+N <= -75 -65 -65 -75 -65 -65 dBFS [20 Hz, 20 KHz] 
Dynamic range with signal present >= 85 80 80 85 80 80 dBFS A-weighted [20 Hz, 20 KHz] 
Magnitude Response <=+- 0.25 0.25 0.25 0.25 0.25 0.25 dB ripple (deviation from center) [20 Hz, 20 KHz] (5)
    Upper band edge limit < 1 1 1 1 1 1 dB [20 Hz, 20 KHz] (5)
    Lower band edge limit < 3 3 3 3 3 3 dB [20 Hz, 20 KHz] (5)
Sampling frequency accuracy < 0.02 0.02 0.02 0.02 0.02 0.02 %  
Full scale input voltage >= 1.000 0.707 1.000 1.000 0.707 1.000 Vrms  
Analog Microphone In Jack                  
THD+N <= -69 -65 -65 -69 -65 -65 dBFS [100 Hz, 20 KHz] 
Dynamic range with signal present >= 80 70 70 80 70 70 dBFS A-weighted [100 Hz, 20 KHz] 
Magnitude Response <=+- 0.25 0.25 0.25 0.25 0.25 0.25 dB ripple (deviation from center) [100 Hz ,20 KHz] (5)
    Upper band edge limit < 1 1 1 1 1 1 dB [100 Hz ,20 KHz] (5)
    Lower band edge limit < 3 3 3 3 3 3 dB [100 Hz ,20 KHz] (5)
Sampling frequency accuracy < 0.02 0.02 0.02 0.02 0.02 0.02 %  
Full scale input voltage >= 0.1 0.07 0.1 0.1 0.07 0.1 Vrms  
(1) For 3.3 V codecs or for codecs on mobile systems regardless of voltage the full scale input and output full scale voltage requirement changes to >= 0.707 Vrms. Speaker output expected to be half into 8 Ohm for 3.3V codecs. More audio fidelity friendly analog power supply voltages in the range of 4V-5V are recommended
(2) DR, FREQUENCY ACCURACY, CROSS-TALK and INTERCHANNEL PHASE DELAY should be measured in accordance with AES-17 audio measurements standards. THD+N will diverge from AES-17 and be tested with a test signal at -3dBFS (DAC) and -3dBFS (ADC) in the context of WLP 3.0. This will change to a test signal at -1dBFS (DAC) and -1dBFS (ADC) for FUTURE requirement date of June 1, 2008 and a test signal at 0dBFS (DAC) for the generation of WLP requirements after that (5.0). At that time PC audio output devices must be able to accept digital 0dBFS input. THD+N will be tested across the full frequency range but out of band harmonics (above 20Khz) will not affect test result. Since poorly designed filters may cause aliasing-generated distortion above 8KHz but below 20Khz measuring this range is still important even though any potential harmonics created above 8KHz are out of band.
(3) Reference level: 1Vrms. Full Scale is defined as a signal that contains samples at the maximum digital value.
(4) The range refers to analyzer bandwidth and the range of the sweeping tone used in measurements. Frequency sweep may not be used in all measurements. The frequency range in the table is for content at 48Khz sampling rate or above. 44.1KHz test content will sweep up to 17.6KHz in the context of WLP 3.0. We will sweep 44.1Khz across the 20Hz – 20KHz envelope for a FUTURE requirement date of June 1, 2008, as is expected to meet Redbook CD fidelity requirements. For Sample Rates at 88.2KHz or higher we recommend 30KHz bandwidth.
(5) Frequency response in the transition band should be monotonic; transition band starts at the point where ripples exceed the magnitude response requirement and ends at the upper 1dB, lower 3dB frequency corner. The ripple value is measured peak to peak defined as the highest positive value and the lowest negative value outside of the transition region. The value +-.25dB ripple means that the delta from peak to peak can be as much as .5dB. FUTURE requirement date of June 1, 2008 will tighten this requirement to +-.125dB ripple peak to peak; meaning the delta between the ripple peaks can be max .25dB outside of the transition region.
(6) These are two examples. Testing will occur at these two endpoints and anywhere within this envelope.

 

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