WM8985
Pre-Production
Test Conditions
DCVDD=1.8V, AVDD1=AVDD2=DBVDD=3.3V, TA = +25oC, 1kHz signal, fs = 48kHz, 24-bit audio data unless otherwise stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
DAC to left and right mixer into headphone 16Ω load on LOUT2 and ROUT2, Class AB mode
LOUT2VOL, ROUT2VOL, DACLVOL and DACRVOL = 0dB
Full-scale output
Signal to Noise Ratio 3
AVDD1/3.3
Vrms
dB
SNR
A-weighted
97
95.5
-79
AVDD1=AVDD2=3.3V
22Hz to 20kHz
dB
dBFS
dBFS
dB
AVDD1=AVDD2=3.3V
Po = 20mW, RL=16Ω
Total Harmonic Distortion 4
Total Harmonic Distortion + Noise 5
Channel Separation 6
THD
-70
THD+N
Po = 20mW, RL=16Ω
-75
TBC
1kHz signal
100
DAC to left and right mixer into headphone 16Ω load on LOUT2 and ROUT2, Class D mode, Lfilter = 33nH Cfilter = 220nf
LOUT2VOL, ROUT2VOL, DACLVOL and DACRVOL = 0Db
Full-scale output
Signal to Noise Ratio 3
AVDD1/3.3
90
Vrms
dB
SNR
THD
A-weighted
80
AVDD1=AVDD2=3.3V
Po = 20mW, RL=16Ω
Total Harmonic Distortion 4
-79
dBFS
Channel Separation 6
PWM Rise Time
PWM Fall Time
1kHz signal
100
1.5
1.5
1.4
72
dB
ns
ns
PWM Switching Frequency
Efficiency
DCLKDIV = 1000
RL = 16Ω, tPW = 20ns,
PO = 20mW
MHz
%
Power Supply Rejection
Idle Current
PSRR
100mVpp ripple @217Hz
injected on AVDD2
70
dB
No analogue output signal
on either channel
0.5
mA
Bypass paths to left and right output mixers. BYPL2LMIX = 1 and BYPR2RMIX = 1
PGA gain range into mixer
Gain adjusted by
BYPLMIXVOL and
BYPRMIXVOL
-15
0
+6
dB
BYPLMIXVOL and BYPRMIXVOL
gain step into mixer
3
dB
dB
Mute attenuation
BYPL2LMIX = 0
BYPR2RMIX = 0
100
Analogue outputs (LOUT1, ROUT1, LOUT2, ROUT2)
Programmable Gain range
Gain adjusted by
L/ROUT1VOL and
L/ROUT2VOL
-57
0
+6
dB
Programmable Gain step size
Mute attenuation
Monotonic
1
dB
dB
1kHz, full scale signal
85
L/ROUT1MUTE = 1
L/ROUT2MUTE = 1
PP, Rev 3.4, October 2006
12
w
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
