WM8903LGEFK/RV Wolfson Microelectronics, WM8903LGEFK/RV Datasheet - Page 43

• Manufacturer Part Number: WM8903LGEFK/RV
• Description: Audio CODECs ULTRA LOW PWR HI FI CODEC
• Manufacturer: Wolfson Microelectronics

Specifications of WM8903LGEFK/RV

• Audio Codec Type: Stereo Codec
• No. Of Adcs: 2
• No. Of Dacs: 2
• No. Of Input Channels: 6
• No. Of Output Channels: 8
• Adc / Dac Resolution: 24bit
• Sampling Rate: 96kHz
• Operating Temperature Range: -40°C To +85°C
• Rohs Compliant: Yes
• Adcs / Dacs Signal To Noise Ratio: 96dB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Pre-Production
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Table 16 DRC Gain Limits
DYNAMIC CHARACTERISTICS
The dynamic behaviour determines how quickly the DRC responds to changing signal levels. Note
that the DRC responds to the average (RMS) signal amplitude over a period of time.
The DRC_ATTACK_RATE determines how quickly the DRC gain decreases when the signal
amplitude is high. The DRC_DECAY_RATE determines how quickly the DRC gain increases when
the signal amplitude is low.
These register fields are described in Table 17. Note that the register defaults are suitable for general
purpose microphone use.
Table 17 DRC Time Constants
R41(29h)
DRC 1
R41 (29h)
DRC 1
REGISTER
REGISTER
ADDRESS
ADDRESS
15:12
11:8
BIT
3:2
1:0
BIT
DRC_MINGAIN
[1:0]
DRC_MAXGAIN
[1:0]
DRC_ATTACK_
RATE [3:0]
DRC_DECAY_R
ATE [3:0]
LABEL
LABEL
DEFAULT
DEFAULT
0011
0010
00
01
Minimum gain the DRC can use to
attenuate audio signals
00 = 0dB (default)
01 = -6dB
10 = -12dB
11 = -18dB
Maximum gain the DRC can use to
boost audio signals
00 = 12dB
01 = 18dB (default)
10 = 24dB
11 = 36dB
Gain attack rate (seconds/6dB)
0000 = instantaneous
0001 = 363us
0010 = 726us
0011 = 1.45ms (default)
0100 = 2.9ms
0101 = 5.8ms
0110 = 11.6ms
0111 = 23.2ms
1000 = 46.4ms
1001 = 92.8ms
1010 = 185.6ms
1011-1111 = Reserved
Gain decay rate (seconds/6dB)
0000 = 186ms
0001 = 372ms
0010 = 743ms (default)
0011 = 1.49s
0100 = 2.97s
0101 = 5.94s
0110 = 11.89s
0111 = 23.78s
1000 = 47.56s
1001-1111 = Reserved
PP, Rev 3.1, August 2009
DESCRIPTION
DESCRIPTION
WM8903
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