POWER SUPPLIES AND REFERENCES (Continued)

Name

Pin

I / O

Functional Description

AFILT2

30

O

This pin is not used and should be left open (NC). However, a capacitor to ground on this pin

is permitted - it will not affect performance.

3DP, 3DN

33,34

O

These pins are used to complete the National 3D Sound circuit. Connect a 0.022µF capacitor

between pins 3DP and 3DN. The National 3D Sound can be turned on and off via bit D13 in

control register 20h. This is a fixed-depth type stereo enhance circuit, thus writing to register

22h has no effect. If National 3D Sound is not needed, then these pins should be left as no

connect (NC).

Typical Performance Characteristics

ADC Noise Floor

DAC Noise Floor

10097215

10097216

Analog Loopthru

Noise Floor

ADC Frequency

Response

10097218

10097219

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