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STA308

1.0 PIN DESCRIPRTION

1.1 MVO: Master Volume Override

This pin enables the user to bypass the Volume Control on all channels. When MVO is pulled High, the Master

Volume Register is set to 00h, which corresponds to its Full Scale setting. The Master Volume Register Setting

offsets the individual Channel Volume Settings, which default to 0dB.

1.2 SDI_12 through 78: Serial Data In

Audio information enters the device here. Six format choices are available including I2S, left- or right-justified,

LSB or MSB first, with word widths of 16, 18, 20 and 24 bits.

1.3 RESET

Driving this pin (low) turns off the outputs and returns all settings to their defaults.

1.4 I2C

The SA, SDA and SCL pins operate per the Philips I2C specification. See Section 2.

1.5 PLL: Phase Locked Loop

The phase locked loop section provides the System Timing Signals and CKOUT.

1.6 CKOUT: Clock Out

System synchronization and master clocks are provided by the CKOUT.

1.7 OUT1 through OUT8: PWM Outputs

The PWM outputs provide the input signal for the power devices.

1.8 EAPD: External Amplifier Power-Down

This signal can be used to control the power-down of DDX power devices.

1.9 SDO_12 through 78: Serial Data Out

Audio information exits the device here. Six different format choices are available including I2S, left- or right-

justified, LSB or MSB first, with word widths of 16, 18, 20 and 24 bits.

1.10 PWDN: Device Power-Down

This puts the STA308 into a low-power state via appropriate power-down sequence. Pulling PWDN low begins

power-down sequence, and EAPD goes low ~30ms later.

2.0 II2C BUS SPECIFICATION

The STA308 supports the I2C protocol. This protocol defines any device that sends data on to the bus as a

transmitter and any device that reads the data as a receiver. The device that controls the data transfer is known

as the master and the other as the slave. The master always starts the transfer and provides the serial clock

for synchronization. The STA308 is always a slave device in all of its communications.