WM8720

Production Data

WOLFSON MICROELECTRONICS LTD

PD Rev 3.0 November 2000

4

ELECTRICAL CHARACTERISTICS

Test Conditions

PARAMETER

SYMBOL

TEST CONDITIONS

MIN

TYP

MAX

UNIT

DAC Circuit Specifications

SNR (Note 1)

AVDD, DVDD = 5V

95

102

dB

AVDD, DVDD = 3.3V

100

dB

THD

0dB FS

-96

-85

dB

Dynamic range

THD+N @ -60dB FS

95

102

dB

Passband

±0.25dB

0.4535

fs

Stopband

-3dB

0.491

fs

Pass band ripple

±0.25

dB

Out of band rejection

-40

dB

Channel Separation

98

dB

Gain mismatch

channel-to-channel

0dB FS

±0.5

±5

%FSR

Digital Logic Levels

Input LOW level

0.8

V

Input HIGH level

2.0

V

Output LOW level

Output HIGH level

AVDD - 0.3V

Analogue Output Levels

Output level

Into 10kohm, full scale 0dB,

(5V supply)

1.1

Into 10kohm, full scale 0dB,

(3.3V supply)

0.72

To midrail or AC coupled

(5V supply)

1

kohms

Minimum resistance load

To midrail or AC coupled

(3.3V supply)

1

kohms

Maximum capacitance

load

5V or 3.3V

100

pF

Output DC level

AVDD/2

V

Reference Levels

Potential divider

resistance

AVDD to CAP and CAP to AGND

90

kohms

Voltage at CAP

AVDD/2

POR

POR threshold

2.0

V

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.

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

3.

THD+N (dB) is a ratio of the r.m.s. 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) 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.

6.

Pass-Band Ripple - Any variation of the frequency response in the pass-band region.