WM8976 Wolfson Microelectronics Ltd., WM8976 Datasheet - Page 7

• Manufacturer Part Number: WM8976
• Description: The WM8976 is a low power, high quality stereo codec designed for portable applications such as Digital still camera or Digital Camcorde
• Manufacturer: Wolfson Microelectronics Ltd.

Pre-Production
ELECTRICAL CHARACTERISTICS
w
Test Conditions
DCVDD=1.8V, AVDD=DBVDD=SPKVDD= 3.3V, T
stated.
PARAMETER
Microphone Preamp Inputs (LIP, LIN, RIP)
Full-scale Input Signal Level –
note this changes in proportion
to AVDD (Note 1)
Mic PGA equivalent input noise
Input resistance
MIC Programmable Gain Amplifier (PGA)
Programmable Gain
Programmable Gain Step Size
Mute Attenuation
Selectable Input Gain Boost (0/+20dB)
Gain Boost on PGA input
Gain range from AUXL or L2
input to boost/mixer
Gain step size to boost/mixer
Auxilliary Analogue Inputs (AUXL, AUXR)
Full-scale Input Signal Level
(0dB) – note this changes in
proportion to AVDD
Input Capacitance
Automatic Level Control (ALC)
Target Record Level
Programmable gain
Gain Hold Time (Note 3,5)
Gain Ramp-Up (Decay) Time
(Note 4,5)
Gain Ramp-Down (Attack) Time
(Note 4,5)
Mute Attenuation
Analogue to Digital Converter (ADC)
Signal to Noise Ratio (Note 6)
Total Harmonic Distortion
(Note 7)
At 35.25dB
SYMBOL
C
R
R
R
R
C
V
V
t
SNR
THD
gain
t
HOLD
t
MICIN
MICIN
MICIN
MICIP
MICIN
MICIN
DCY
ATK
INFS
INFS
Guaranteed monotonic
A
ALCMODE=1 (limiter),
ALCMODE=1 (limiter),
A-weighted, 0dB gain
ALCMODE=0 (ALC),
ALCMODE=0 (ALC),
MCLK = 12.288MHz
Gain set to 35.25dB
TEST CONDITIONS
INPPGAVOL = 0dB
PGABOOST = 0dB
L/RIP2INPPGA = 1
MCLK=12.288MHz
MCLK=12.288MHz
MCLK=12.288MHz
MCLK=12.288MHz
= +25
Gain set to -12dB
Gain set to 0dB
Boost disabled
Boost enabled
-3dBFS input
0 to 20kHz
(Note 3)
(Note 3)
(Note 3)
(Note 3)
(Note 3)
o
C, 1kHz signal, fs = 48kHz, 24-bit audio data unless otherwise
-22.5
MIN
-12
-12
-12
0, 2.67, 5.33, 10.67, … , 43691
(time doubles with each step)
(time doubles with each step)
(time doubles with each step)
(time doubles with each step)
(time doubles with each step)
0.73, 1.45, 2.91, … , 744
0.83, 1.66, 3.33, … , 852
0.18, 0.36, 0.73, … , 186
3.3, 6.6, 13.1, … , 3360
AVDD/3.3
0.75
TYP
150
120
1.0
1.6
120
-84
47
75
94
10
20
10
95
0
0
3
0
35.25
35.25
MAX
-1.5
PP Rev 3.0 April 2006
+6
WM8976
Vrms
Vrms
UNIT
dBV
dBV
k
k
k
k
ms
ms
ms
uV
pF
dB
dB
dB
dB
dB
dB
dB
pF
dB
dB
dB
dB
7