WM8776SEFT/V Wolfson Microelectronics, WM8776SEFT/V Datasheet - Page 36

• Manufacturer Part Number: WM8776SEFT/V
• Description: Audio CODECs Stereo CODEC with 5-Ch Mux
• Manufacturer: Wolfson Microelectronics

Specifications of WM8776SEFT/V

• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: TQFP-48
• Minimum Operating Temperature: - 25 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

WM8776
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TRANSIENT WINDOW (LIMITER ONLY)
To prevent the limiter responding to to short duration high ampitude signals (such as hand-claps in a
live performance), the limiter has a programmable transient window preventing it responding to
signals above the threshold until their duration exceeds the window period. The Transient window is
set in register TRANWIN.
ZERO CROSS
The PGA has a zero cross detector to prevent gain changes introducing noise to the signal. In ALC
mode the register bit ALCZC allows this to be turned off if desired.
Limiter Control
ALC Control 2
REGISTER
ADDRESS
R18 (12h)
REGISTER
REGISTER
Control 3
ADDRESS
ADDRESS
0010010
R20 (14h)
R17 (11h)
0010100
0010001
ALC
BIT
3:0
7:4
BIT
BIT
6:4
7
DCY [3:0]
ATK[3:0]
LABEL
TRANWIN
LABEL
LABEL
ALCZC
[2:0]
DEFAULT
0010
0011
DEFAULT
DEFAULT
(disabled)
010
0
ALC mode
0000: 8.4ms
0001: 16.8ms
0010: 33.6ms…
(time doubles with
every step)
1010 or higher:
8.6s
ALC mode
0000: 33.5ms
0001: 67.2ms
0010: 134.4ms
….(time doubles for
every step)
1010 or higher:
34.3ms
LC attack (gain ramp-down) time
Length of Transient Window
000: 0us (disabled)
001: 62.5us
010: 125us
…..
111: 4ms
PGA zero cross enable
0 : disabled
1: enabled
LC decay (gain ramp-up) time
DESCRIPTION
DESCRIPTION
DESCRIPTION
PD, Rev 4.1, September 2008
Limiter Mode
0000: 250us
0001: 500us… 0010:
1ms
(time doubles with
every step)
1010 or higher: 256ms
Limiter mode
0000: 1.2ms
0001: 2.4ms
0010: 4.8ms ….(time
doubles for every
step)
1010 or higher:
1.2288s
Production Data
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