MOSA

MS6821

4 Stereo inputs / 2W PA output integrated Audio DAC and Volume Control

REV 1.0

19

www.mosanalog.com

OPERATION PROCEDURE

The sequence of operation: power on→ activating → power down → activating → power off. The basic flowcharts are

as follows:

For HP mode and HP/BTL mode

Volume Down To Mute

Input Channels Mute On

[ Attenuation and Mute ]

Code: Lch 00111111 (3Fh)

Rch 01111111 (7Fh)

Power Off

Power Off

Power On

Power On

Activating

Power Down

(Shut Down)

Power Down Preparation

[ Power Down Mode]

Code: 11000010 (C2h)

[ Input4 & Gain = 0dB]

Code: Lch 10000011 (83h)

Rch 10100011 (a3h)

wait 7 sec

Power Down All The Devices

Pull Down CAP Pin To Ground

[ Power Down Mode]

Code: 11011111 (DFh)

Keep All The Digital Interface

Signals Unchanged

Disable Power Down

[ Power Down Mode]

Code: 11000010 (C2h)

Wait 0.5 sec

Setting Input Gain IsFixed

[ Enable Input & Input Gain ]

Code: Lch 100xxx00

Rch 101xxx00

Power Down All The Devices

Only CAPPD Keep Activating

[ Power Down Mode ]

Code: 11011110 (DEh)

Volume Down To Mute

Input Channels Mute On

[ Attenuation and Mute ]

Code: Lch 00111111 (3Fh)

Rch 01111111 (7Fh)

PDPR = 0

[ Power Down Mode]

Code: 11000000 (C0h)

Wait 0.5 sec

Mute Off And Volume Up/Down

Step By Step

[ Attenuation and Mute ]

Code: Lch 00xxxxxx

Rch 01xxxxxx

Power Down Preparation

[ Power Down Mode ]

Code: 11000010 (C2h)

[ Input4 & Gain = 0dB]

Code: Lch 10000011 (83h)

Rch 10100011 (a3h)

wait 7 sec

Default Status

[Attenuation & Mute]

Mute on (max attenuation)

[ Input Selector & Input Gain ]

L-ch1, R-ch1

0dB

[ Power Down Mode]

All power down status

[ Output Mode & Mixer & Format ]

BTL mode

Inputs not mixed with DAC signal

RJF format

All the Digital Interface Signals

Pull Low

I2C pull low

Audio inputs pull low

(BCK, WS, DATA)

All the Digital Interface Signals

Pull Low

I2C pull low

Audio inputs pull low

(BCK, WS, DATA)