Pre-Production

WM8785

w

PP Rev 3.0 December 2005

7

Test Conditions

unless otherwise stated.

PARAMETER

SYMBOL

TEST CONDITIONS

MIN

TYP

MAX

UNIT

Supply Current

Analogue supply current

27

mA

Digital supply current

5

mA

Power Down

22

uA

Note:

1.

VMID is decoupled with 10uF and 0.1uF capacitors close to the device package. Smaller capacitors may reduce

performance.

TERMINOLOGY

1.

Signal-to-noise ratio (dB) – Ratio of output level with 1kHz full scale input, to the output level with all zeros into the

digital input, over a 20Hz to 20kHz bandwidth. (No Auto-zero or Automute function is employed in achieving these

results).

2.

Dynamic range (dB) - DR 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.

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.

5.

All performance measurements are done with a 20kHz low pass filter, and where noted an A-weight filter, except

where noted. Failure to use such a filter will result in higher THD+N and lower SNR and Dynamic Range readings than

are found in the Electrical Characteristics. The low pass filter removes out of band noise; although this is not audible,

it may affect dynamic specification values