Cirrus Logic WM8940 Manual page 10

Test Conditions
DCVDD = 1.8V, AVDD = DBVDD = 3.3V, SPKVDD =3.3V, T
stated.
PARAMETER
Digital to Analogue Converter (DAC) to MONO Output with 10k / 50pF load and DACVOL 0dB
1
Full-scale output
3
Signal to Noise Ratio
4
Total Harmonic Distortion
Total Harmonic Distortion + Noise
6
Channel Separation
MICP and MICN input PGA to input boost stage into 10k / 50pF load on SPKOUTP and SPKOUTP
INPPGAVOL, PGABOOST = 0dB
Full-scale output voltage, 0dB gain
3
Signal to Noise Ratio
4
Total Harmonic Distortion
Total Harmonic Distortion + Noise
6
Channel Separation
DAC to Speaker Output (SPKOUTP, SPKOUTN with 8 bridge tied load) Bypass mode
Output Power
4
Total Harmonic Distortion
3
Signal to Noise Ratio
Power Supply Rejection Ratio
(50Hz-22kHz)
AUX In to Headphone Output (SPKOUTP, SPKOUTN with 16R resistive load to GND) Bypass mode
3
Signal to Noise Ratio
4
Total Harmonic Distortion
Microphone Bias
Bias Voltage
Bias Current Source
Output Noise Voltage
Digital Input / Output
Input HIGH Level
Input LOW Level
Output HIGH Level
Output LOW Level
Input Capacitance
10
= +25
A
SYMBOL TEST CONDITIONS
DACVOL = 0dB
SNR A-weighted
AVDD=SPKVDD=3.3V
THD 0dBFS input
AVDD=SPKVDD=3.3V
5
THD+N 0dBFS input
AVDD=SPKVDD=3.3V
1kHz signal
SNR A-weighted
AVDD=SPKVDD=3.3V
THD full-scale signal
AVDD=SPKVDD=3.3V
5
THD+N full-scale signal
AVDD=SPKVDD=3.3V
Po Output power is closely correlated with THD see below
THD Po=350mW, RL = 8Ω
SPKVDD=3.3V
SNR A-weighted
SPKVDD=3.3V
PSRR
R = 8 BTL
L
SNR A-weighted
SPKVDD=3.3V
THD Po=20mW, RL = 16Ω
SPKVDD=3.3V
MBVSEL=0
MBVSEL=1
for V
MICBIAS
1kHz to 20kHz
V
IH
V
IL
V I
OH OL
V I
OL OH
All digital pins
o
C, 1kHz signal, fs = 48kHz, 24-bit audio data unless otherwise
MIN
AVDD/3.3
93
SPKVDD/3.3
94
0.03
93.5
95
0.9*AVDD
0.65*AVDD
within +/-3%
0.7
DBVDD
=1mA 0.9
DBVDD
-1mA
WM8940
TYP MAX UNIT
V
rms
98 dB
-80 -75 dBFS
-78 -74 dBFS
100 dB
V
rms
99 dB
-85 dBFS
-90
-82 dBFS
-87
100 dB
%
-60 dB
-70
98 dB
50 dB
99 dB
0.02 -67 %
dB
-74
V
V
3 mA
15 nV/Hz
V
0.3DBVDD V
V
0.1xDBVDD V
10 pF
Rev 4.4