WM8976CGEFLSLASHV datasheet(79/114 Pages) WOLFSON

79 / 114 page

Production Data

WM8976

PD, Rev 4.5, November 2011

POWER SUPPLIES

The WM8976 can use up to four separate power supplies:



AVDD and AGND: Analogue supply, powers all analogue functions except the speaker output

and mono output drivers. AVDD can range from 2.5V to 3.6V and has the most significant

impact on overall power consumption (except for power consumed in the headphone). A large

AVDD slightly improves audio quality.



SPKVDD and SPKGND: Headphone and Speaker supplies, power the speaker and mono

output drivers. SPKVDD can range from 2.5V to 5V. SPKVDD can be tied to AVDD, but it

requires separate layout and decoupling capacitors to curb harmonic distortion. With a larger

SPKVDD, louder headphone and speaker outputs can be achieved with lower distortion. If

SPKVDD is lower than AVDD, the output signal may be clipped.



DCVDD: Digital core supply, powers all digital functions except the audio and control interfaces.

DCVDD can range from 1.71V to 3.6V, and has no effect on audio quality. The return path for

DCVDD is DGND, which is shared with DBVDD.



DBVDD can range from 1.71V to 3.6V. DBVDD return path is through DGND.

It is possible to use the same supply voltage for all four supplies. However, digital and analogue

supplies should be routed and decoupled separately on the PCB to keep digital switching noise out of

the analogue signal paths.

DCVDD should be greater than or equal to 1.9V when using the PLL.

WM8976CGEFL/V Datasheet(PDF) 79 Page - Wolfson Microelectronics plc