WM8720
ELECTRICAL CHARACTERISTICS
Test Conditions
AVDD, DVDD = 5V, AGND, DGND = 0V, T
A
= +25
o
C, fs = 48kHz, SCKI = 256fs unless otherwise stated.
PARAMETER
DAC Circuit Specifications
SNR (Note 1)
THD
Dynamic range
Passband
Stopband
Pass band ripple
Out of band rejection
Channel Separation
Gain mismatch
channel-to-channel
Digital Logic Levels
Input LOW level
Input HIGH level
Output LOW level
Output HIGH level
Analogue Output Levels
Output level
Into 10kohm, full scale 0dB,
(5V supply)
Into 10kohm, full scale 0dB,
(3.3V supply)
Minimum resistance load
To midrail or AC coupled
(5V supply)
To midrail or AC coupled
(3.3V supply)
Maximum capacitance
load
Output DC level
Reference Levels
Potential divider
resistance
Voltage at CAP
POR
POR threshold
2.0
AVDD to CAP and CAP to AGND
90
AVDD/2
5V or 3.3V
1.1
0.72
1
1
100
AVDD/2
V
IL
V
IH
V
OL
V
OH
I
OL
= 2mA
I
OH
= 2mA
AVDD - 0.3V
2.0
0.8
0dB FS
AVDD, DVDD = 5V
AVDD, DVDD = 3.3V
0dB FS
THD+N @ -60dB FS
±0.25dB
-3dB
0.491
±0.25
-40
98
±0.5
±5
95
95
102
100
-96
102
-85
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
Production Data
UNIT
dB
dB
dB
dB
fs
fs
dB
dB
dB
%FSR
0.4535
V
V
AV
SS
+ 0.3V
V
RMS
V
RMS
kohms
kohms
pF
V
kohms
V
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.
WOLFSON MICROELECTRONICS LTD
PD Rev 3.0 November 2000
4
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
