Electrical Characteristics - Cirrus Logic WM8940 Manual

ELECTRICAL CHARACTERISTICS

Test Conditions
DCVDD = 1.8V, AVDD = DBVDD = 3.3V, SPKVDD =3.3V, T
stated.
PARAMETER
Microphone Input PGA Inputs (MICN, MICP)
INPPGAVOL and PGABOOST = 0dB
Full-scale Input Signal Level – Single-
1
ended input via LIN/RIN
Full-scale Input Signal Level –
1,2
Pseudo-differential input
Input PGA equivalent input noise
MICN input resistance
MICN input resistance
MICN input resistance
MICP input resistance
Input Capacitance
Maximum Input PGA Programmable
Gain
Minimum Input PGA Programmable
Gain
Programmable Gain Step Size
Input PGA Mute Attenuation
Input Gain Boost
Input Gain Boost
Auxiliary Analogue Inputs (AUX)
Full-scale Input Signal Level
Input Resistance
Input Capacitance
Maximum Gain from AUX input PGA
mixers
Minimum Gain from AUX input PGA
mixers
AUX2BOOSTVOL step size
Analogue to Digital Converter (ADC) - Input from MICN and MICP in differential configuration to input PGA
INPPGAVO, PGABOOST and ADCVOL = 0dB
3
Signal to Noise Ratio
4
Total Harmonic Distortion
Total Harmonic Distortion + Noise
6
Channel Separation
Rev 4.4
SYMBOL TEST CONDITIONS
INPPGAVOL = +35.25dB
No input signal
INPPGAVOL = +35.25dB
INPPGAVOL = 0dB
INPPGAVOL = -12dB
All gain settings
All analogue input pins
Gain adjusted by
Gain adjusted by
Guaranteed monotonic
INPPGAMUTE
PGABOOST= 0
PGABOOST = 1
2
Input boost and mixer
enabled, at 0dB gain
All analogue Inputs
Gain adjusted by
AUX2BOOSTVOL
Gain adjusted by
AUX2BOOSTVOL
Guaranteed monotonic
SNR
THD
5
THD+N
1kHz full scale input signal
o
= +25 C, 1kHz signal, fs = 48kHz, 24-bit audio data unless otherwise
A
MIN
0 to 20kHz
+33.25
INPPGAVOL
-14
INPPGAVOL
+4.0
-14
A-weighted 88
AVDD=3.3V
-1dBV Input
AVDD=3.3V
-1dBV Input
AVDD=3.3V
WM8940
TYP MAX UNIT
AVDD/3.3 V
AVDD*0.7/ V
3.3
76.5 dB
2 k
58.5 k
k
97.5
124.5 k
10 pF
+35.25 +37.25 dB
-12 -10 dB
0.75 dB
92 dB
0 dB
+20
dB
AVDD/3.3 V
20 k
10
pF
+6 +7.5
dB
-12 -9 dB
3 dB
91 dB
-80 -75 dB
-75 -68 dB
100 dBFS
rms
rms
rms
9