WM8727

Production Data

w

PD Rev 4.1 April 2004

6

TERMINOLOGY

1.

Signal-to-noise ratio (dB) - SNR is a measure of the difference in level between the full scale output and the output with no

signal applied. (No Auto-zero or Automute function is employed in achieving these results).

2.

Dynamic range (dB) - DNR is a measure of the difference between the highest and lowest portions of a signal. Normally a

THD+N measurement at 60dB below full scale. The measured signal is then corrected by adding the 60dB to it. (e.g.

THD+N @ -60dB= -32dB, DR= 92dB).

3.

THD+N (dB) - THD+N is a ratio, of the rms values, of (Noise + Distortion)/Signal.

4.

Stop band attenuation (dB) - Is the degree to which the frequency spectrum is attenuated (outside audio band).

5.

Channel Separation (dB) - Also known as Cross-Talk. This is a measure of the amount one channel is isolated from the

other. Normally measured by sending a full scale signal down one channel and measuring the other.

MASTER CLOCK TIMING

MCLK

t

MCLKL

t

MCLKH

t

MCLKY

Figure 1 Master Clock Timing Requirements

Test Conditions

PARAMETER

SYMBOL

TEST CONDITIONS

MIN

TYP

MAX

UNIT

System Clock Timing Information

MCLK Master clock pulse width high

8

ns

MCLK Master clock pulse width low

8

ns

MCLK Master clock cycle time

20

ns

MCLK Duty cycle

40:60

60:40

Time from MCLK stopping to power

down.

1.5

12

µs

DIGITAL AUDIO INTERFACE

BCKIN

LRCIN

t

BCH

t

BCL

t

BCY

DIN

t

LRSU

t

DS

t

LRH

t

DH

Figure 2 Digital Audio Data Timing