WM8734 ETC-unknow, WM8734 Datasheet - Page 6

• Manufacturer Part Number: WM8734
• Description: Stereo Audio Codec
• Manufacturer: ETC-unknow

WM8734
Notes:
1.
2.
3.
4.
TERMINOLOGY
1.
2.
3.
4.
5.
6.
w
Test Conditions
AVDD, DBVDD = 3.3V, AGND = 0V, DCVDD = 3.3V, DGND = 0V, T
otherwise stated.
PARAMETER
Line Output for DAC Playback Only (Load = 47k ohms. 50pF)
0dBfs Full scale output voltage
SNR (Note 1,2,3)
SNR (Note 1,2,3)
SNR (Note 1,2,3)
Dynamic Range (Note 3)
THD
Power Supply Rejection Ratio
DAC channel separation
Ratio of output level with 1kHz full scale input, to the output level with the input short circuited, measured ‘A’ weighted
over a 20Hz to 20kHz bandwidth using an Audio analyser.
Ratio of output level with 1kHz full scale input, to the output level with all zeros into the digital input, measured ‘A’
weighted over a 20Hz to 20kHz bandwidth.
All performance measurements done with 20kHz low pass filter, and where noted an A-weight filter. Failure to use
such a filter will result in higher THD+N and lower SNR and Dynamic Range readings than are found in the Electrical
Characteristics. The low pass filter removes out of band noise; although it is not audible it may affect dynamic
specification values.
VMID decoupled with 10uF and 0.1uF capacitors (smaller values may result in reduced performance).
Signal-to-noise ratio (dB) - SNR is a measure of the difference in level between the full scale output and the output
with no signal applied. (No Auto-zero or Automute function is employed in achieving these results).
Dynamic range (dB) - DNR is a measure of the difference between the highest and lowest portions of a signal.
Normally a THD+N measurement at 60dB below full scale. The measured signal is then corrected by adding the 60dB
to it. (e.g. THD+N @ -60dB= -32dB, DR= 92dB).
THD+N (dB) - THD+N is a ratio, of the rms values, of (Noise + Distortion)/Signal.
Stop band attentuation (dB) – Is the degree to which the frequency spectrum is attenuated (outside audio band).
Channel Separation (dB) - Also known as Cross-Talk. This is a measure of the amount one channel is isolated from
the other. Normally measured by sending a full scale signal down one channel and measuring the other.
Pass-Band Ripple – Any variation of the frequency response in the pass-band region.
SYMBOL
PSSR
DNR
A-weighted, -60dB full
TEST CONDITIONS
At LINE outputs
1kHz 100mVpp
20Hz to 20kHz
@ fs = 48kHz
@ fs = 48kHz,
AVDD = 2.7V
@ fs = 96kHz
1kHz, -3dBfs
1kHz, 0dBfs
A-weighted,
A-weighted,
A-weighted
scale input
100mVpp
A
= +25
o
C, Slave Mode, fs = 48kHz, MCLK = 256fs unless
90
85
MIN
AVDD/3.3
1.0 x
TYP
100
100
-88
-92
98
93
95
50
45
AI Rev 2.2 November 2001
Advanced Information
-80
MAX
Vrms
UNIT
dB
dB
dB
dB
dB
dB
dB
dB
dB
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