Typical Application

APPLICATION HINTS

•

The LM4549B must be initialized by using RESET# to perform a Power On Reset as shown in the Power On Reset Timing

Diagram

•

Don’t leave unused Analog inputs floating. Tie all unused inputs together and connect to Analog Ground through a capacitor

(e.g. 0.1 µF)

•

Do not leave CD_GND floating when using the CD stereo input. CD_GND is the AC signal reference for the CD channels and

should be connected to the CD source ground (Analog Ground may also be acceptable) througha1µF capacitor

•

If using a non-standard AC Link controller take care to keep the SYNC and SDATA_IN signals low during Cold Reset to avoid

entering the ATE or Vendor test modes by mistake.

•

The PC_Beep input should be muted if not used since it defaults to 0 dB gain on reset, unlike the mute default of the other

analog inputs

20123503

FIGURE 1. LM4549B Typical Application Circuit, Single Codec, 1 Vrms inputs

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