WM8739 / WM8739L
ELECTRICAL CHARACTERISTICS
Advanced Information
Test Conditions
AVDD, DBVDD = 3.3V, AGND = 0V, DCVDD = 3.3V, DGND = 0V, T
A
= +25
o
C, Slave Mode, fs = 48kHz, XTI/MCLK = 256fs
unless otherwise stated.
PARAMETER
Digital Logic Levels (CMOS Levels)
Input LOW level
Input HIGH level
Output LOW
Output HIGH
Analogue Reference Levels
Reference voltage
Potential divider resistance
Input to ADC
Input Signal Level (0dB)
V
INLINE
AVDD = 3.3V
AVDD = 1.8V
(WM8739 only)
Signal to Noise Ratio (Note 1,2)
SNR
A-weighted, 0dB gain
A-weighted, 0dB gain
@ fs = 96kHz
A-weighted, 0dB gain,
AVDD = 2.7V
A-weighted, 0dB gain,
AVDD = 1.8V
(WM8739L only)
Dynamic Range (Note 2)
Total Harmonic Distortion
DNR
THD
A-weighted, -60dBV
-1dBV input, 0dB gain
-10dBV, 0dB gain
ADC channel separation
Programmable Gain
Programmable Gain Step Size
Mute attenuation
Input Resistance
Input Capacitance
R
INLINE
C
INLINE
0dB, 1kHz input
0dB gain
12dB gain
20k
10k
1kHz input
1kHz input
Rsource < 50 Ohms
-34.5
85
85
1.0
0
0.316
-10
90
90
88
76
0.545
-5.27
Vrms
dB
Vrms
dBV
dB
dB
dB
dB
V
VMID
R
VMID
AVDD/2
50K
V
Ohms
V
IL
V
IH
V
OL
V
OH
0.9 x VDD
0.7 x VDD
0.1 x VDD
0.3 x VDD
V
V
V
V
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
90
-84
0.006
-74
0.02
90
0
1.5
80
30k
15k
10
+12
-74
0.02
dB
dB
%
dB
%
dB
dB
dB
dB
Ohms
Ohms
pF
Notes
1.
2.
Ratio of output level with 1kHz full scale input, to the output level with all zero’s into the digital input over a 20Hz to
20kHz bandwidth using an Audio analyser.
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).
3.
AI Rev 2.2 September 2001
5
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
