WM8775
Production Data
ELECTRICAL CHARACTERISTICS
Test Conditions
AVDD = 5V, DVDD = 3.3V, AGND = 0V, DGND = 0V, TA = +25oC, fs = 48kHz, MCLK = 256fs unless otherwise stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Digital Logic Levels (TTL Levels)
Input LOW level
VIL
VIH
0.8
V
V
V
V
Input HIGH level
2.0
Output LOW
VOL
VOH
I
OL=1mA
0.1 x DVDD
Output HIGH
IOH=1mA
0.9 x DVDD
Analogue Reference Levels
Reference voltage
VVMID
RVMID
AVDD/2
50k
V
Potential divider resistance
ADC Performance
Input Signal Level (0dB)
Ω
1.0 x
AVDD/5
102
Vrms
dB
SNR (Note 1,2)
SNR (Note 1,2)
A-weighted, 0dB gain
@ fs = 48kHz
97
A-weighted, 0dB gain
@ fs = 96kHz
99
dB
64xOSR
Dynamic Range (note 2)
A-weighted, -60dB
full scale input
102
dB
Total Harmonic Distortion (THD)
1 kHz, 0dBFs
1kHz, -1dBFs
1kHz Input
-92
-95
90
dB
dB
dB
dB
dB
-85
ADC Channel Separation
Programmable Gain Step Size
Programmable Gain Range
(Analogue)
0.25
-21
0.5
0.75
+24
1kHz Input
1kHz Input
Programmable Gain Range
(Digital)
-82
+0
dB
dB
Analogue Mute Attenuation
(Note 5)
1kHz Input, 0dB gain
1kHz 100mVpp
76
Power Supply Rejection Ratio
PSRR
50
45
dB
dB
20Hz to 20kHz
100mVpp
Supply Current
Analogue supply current
Digital supply current
AVDD = 5V
48
mA
mA
DVDD = 3.3V
4.5
Notes:
1. Ratio of output level with 1kHz full scale input, to the output level with all zeros into the digital input, measured ‘A’
weighted.
2. 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.
3. VMID decoupled with 10uF and 0.1uF capacitors (smaller values may result in reduced performance).
4. All performance measurement done using certain timing conditions (please refer to section ‘Digital Audio Interface’).
5. A full digital MUTE can be achieved if the ADC gain (LAG/RAG) is set to minimum.
PD Rev 4.1, June 2006
6
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
