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ESS TECHNOLOGY, INC. 109 Bonaventura Drive, San Jose, CA 95134, USA Tel (408) 643-8800 WWW.ESSTECH.COM

COM

11

ES9018S Product Datasheet

Feature Descriptions

Soft Mute

When Mute is asserted the output signal will ramp to the – level. When Mute is reset the attenuation level will ramp back up to the previous level set

by the volume control register. Asserting Mute will not change the value of the volume control register. The ramp rate is 0.0078125 x fs dB/s, where

fs = DATA_CLK / 64 in PCM serial or DSD modes, or SPDIF sampling rate in SPDIF mode.

Automute

During an automute condition the ramping of the volume of each DAC to – can now be programmatically enabled or disabled.

o

In PCM serial mode, “AUTOMUTE” will become active once the audio data is continuously below the threshold set by <Register Automute_lev>,

for a length of time defined by 2096896 / (<Register#9> x DATA_CLK) Seconds.

o

In SPDIF mode, “AUTOMUTE” will become active once the audio data is continuously below the threshold set by <Register Automute_lev>, for

a length of time defined by 2096896 / (<Register#9> x (64 x Fs) Seconds, where Fs is the SPDIF sampling rate.

o

In the DSD Mode, “AUTOMUTE” will become active when any 8 consecutive values in the DSD stream have as many 1’s and 0’s for a length of

time defined by 2096896 / (<Register Automute_time> x DATA_CLK) Seconds. The following table summarizes the conditions.

Mode

Detection Condition

Time

PCM

Data is continuously lower than <Register

Automute_lev>

2096896 / (<Register Automute_time > x DATA_CLK)

SPDIF

Data is continuously lower than <Register

Automute_lev>

2096896 / (<Register Automute_time > x (64 x Fs))

where Fs is the SPDIF sampling rate

DSD

Equal number of 1s and 0s in every 8 bits of

data

2096896 / (<Register Automute_time > x DATA_CLK)

Table 6 - Automute configurations

Volume Control

Each output channel has its own attenuation circuit. The attenuation for each channel is controlled independently. Each channel can be attenuated

from 0dB to –127dB in 0.5dB steps.

Each 0.5dB step transition takes 64 intermediate levels. The result being that the level changes are done using small enough steps so that no

switching noise occurs during the transition of the volume control. When a new volume level is set, the attenuation circuit will ramp softly to the new

level.

Master Trim

The master trim sets the 0dB reference level for the volume control of each DAC. The master trim is programmable via registers 20-23 and is a 32bit

signed number. Therefore it should never exceed 32'h7FFFFFFF (as this is full-scale signed).

All Mono Mode

The SABRE32 can be put into an all mono mode where all eight DACs are driven from the same source. This can be useful for high-end audio

applications. The source data for all eight DACs can be programmatically configured to be either PCM CH1 or CH2.