WM9082

Production Data

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PD, August 2012, Rev 4.1

12

As noted above, the WM9082 Control Codes are only valid when they are transmitted consecutively

for the required number of times. The valid Control Codes can be used to control the operating state

of the WM9082 and also to select different operating modes.

The “Page 2 access” Control Code enables the Page 2 Control Codes for the next control code only;

the Page 1 codes will apply again for any subsequent control code(s).

The state transitions and operating modes are described below.

INITIAL POWER-UP

When a valid CLK signal is first detected on IN1 or IN2, the WM9082 powers up to the “STANDBY”

state. The WM9082 will remain in this state until a “Start-up Event” is detected, or until the CLK signal

is removed.

CONFIGURATION EVENTS

In the STANDBY state, the WM9082 can be configured (if required) using the Control Code

sequences listed in Table 6.

Note that these Control Code sequences are only valid when the WM9082 is in the STANDBY state; it

is not possible to configure the device whilst simultaneously sending audio data.

The following features are configurable in the STANDBY state:



Sample rate (33kHz, 44.1kHz or 48kHz)



Input path High Pass Filter (HPF)



Output slew rate control



Operating Mode (PSRR vs SNR control)

The cut-off frequency of the input path HPF, when enabled, is around 2Hz, assuming a 48kHz audio

sample rate (CLK = 6.144MHz).

The operating mode selections provide different options for SNR vs PSRR optimisation.