WM8716
Notes:
1.
2.
Production Data
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. 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.
Except for Pin 12 (MODE8X) and Pin 17 (DIFFHW), where V
IH
= 2.6V min.
3.
TERMINOLOGY
1.
2.
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.
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. (eg THD+N @ -60dB= -32dB, DR= 92dB).
THD+N (dB) is a ratio of the r.m.s. values, of (Noise + Distortion)/Signal.
Stop band attenuation (dB) is the degree to which the frequency spectrum is attenuated (outside audio band).
Channel Separation (dB) (also known as Cross-Talk) 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.
3.
4.
5.
6.
LRCIN
t
BCH
BCKIN
t
BCY
DIN
t
DS
t
DH
t
BL
t
BCL
t
LB
Figure 1 Audio Data Input Timing
TEST CONDITIONS
AVDD, DVDD = 5V, AGND, DGND = 0V, T
A
= +25
o
C, fs = 48kHz, SCKI = 256fs unless otherwise stated.
PARAMETER
BCKIN pulse cycle time
BCKIN pulse width high
BCKIN pulse width low
BCKIN rising edge
to LRCIN edge
LRCIN rising edge
to BCKIN rising edge
DIN setup time
DIN hold time
SYMBOL
t
BCY
t
BCH
t
BCL
t
BL
t
LB
t
DS
t
DH
TEST CONDITIONS
MIN
100
50
50
30
30
30
30
TYP
MAX
UNIT
ns
ns
ns
ns
ns
ns
ns
Audio Data Input Timing Information
w
PD, Rev 4.2,August 2008
6
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
