WM8580 datasheet(25/97 Pages) WOLFSON

25 / 97 page

Production Data

WM8580

PD Rev 4.3 August 2007

In DSP modes A and B, left and right channels must be time multiplexed and input on the input data

line on the Audio Interface. For the PAIF Receiver, all three left/right DAC channels are multiplexed

on DIN1 (assuming DAC_SEL = 00). LRCLK is used as a frame synchronisation signal to identify the

MSB of the first word. The minimum number of BCLKs per LRCLK period is six times the selected

word length. Any mark to space ratio is acceptable on LRCLK provided the rising edge is correctly

positioned.

LEFT JUSTIFIED MODE

In Left Justified mode, the MSB of the input data is sampled by the WM8580 on the first rising edge

of BCLK following a LRCLK transition. The MSB of the output data changes on the same falling edge

of BCLK as LRCLK and may be sampled on the next rising edge of BCLK. LRCLK is high during the

left samples and low during the right samples.

Figure 14 Left Justified Mode Timing Diagram

RIGHT JUSTIFIED MODE

In Right Justified mode, the LSB of input data is sampled on the rising edge of BCLK preceding a

LRCLK transition. The LSB of the output data changes on the falling edge of BCLK preceding a

LRCLK transition, and may be sampled on the next rising edge of BCLK. LRCLKs are high during the

left samples and low during the right samples.

Figure 15 Right Justified Mode Timing Diagram

WM8580 Datasheet(PDF) 25 Page - Wolfson Microelectronics plc