WM8716
Production Data
MODES OF OPERATION
Control of the various modes of operation is either by software control over the serial interface, or
by hard-wired pin control. Selection of software or hardware mode is via MODE pin. The following
functions may be controlled either via the serial control interface or by hard wiring of the
appropriate pins.
HARDWARE CONTROL MODES
When the MODE pin is held ‘low’ the following hardware modes of operation are available. In
Hardware differential mode or 8X mode some of these modes/control words are altered or
unavailable.
DE-EMPHASIS CONTROL
MDDM1
MCDMO
DE-EMPHASIS
PIN 27
PIN 26
L
L
H
L
Off
L
48kHz
44.1kHz
32kHz
H
H
H
Table 2 De-Emphasis Control
AUDIO INPUT FORMAT
CSBIIS
CSBIWO
DATA FORMAT
PIN 28
PIN 23
L
L
H
L
16 bit normal right justified
20 bit normal right justified
16 bit I2S
L
H
H
H
24 bit I2S
Table 3 Audio Input Format
SOFT MUTE
MUTEB
FUNCTION
PIN 25
L
Mute On (no output)
Automute
Z
H
Mute Off (normal operation)
Table 4 Soft Mute
A logic low on the MUTEB pin will cause the attenuation to ramp to infinite attenuation at a rate of
128/fs seconds per 0.5dB step. Setting MUTEB high will cause the attenuation to ramp back to its
previous value.
Leaving MUTEB undriven allows operation of the automute circuit in both hardware and software
modes. On receiving 1024 consecutive zero value audio samples, the analogue stage output mute is
asserted. This may be overdriven from the MUTEB pin to disable the automute function, or output as
a weak (10kohm) output signal.
w
PD Rev 4.1 September 2006
12
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
