Philips UDA1325

1999 May 10 16

Philips Semiconductors Preliminary speciﬁcation

Universal Serial Bus (USB) CODEC UDA1325

Table 8 ADAC general control registers

Soft mute control

When the mute (bit 1 of control register 0) is active for the playback channel, the value of the sample is decreased

smoothly to zero following a raised cosine curve. There are 32 coefficients used to step down the value of the data, each

one being used 32 times before stepping to the next. This amounts to a mute transition of 23 ms at fs= 44.1 kHz. When

the mute is released, the samples are returned to the full level again following a raised cosine curve with the same

coefficients being used in reversed order.

The mute, on the master channel is synchronized to the sample clock, so that operation always takes place on complete

samples.

Control register 0 0 reset ADAC 0 = not reset

1 = reset

1 soft mute control 0= not muted

1 = mutes

2 synchronous/asynchronous 0= asynchronous

1 = synchronous select 0

3 channel manipulation 0= L -> L, R -> R

1=L->R, R->L

4 de-emphasis 0= de-emphasis off

1 = de-emphasis on

6 and 5 audio mode 00 = ﬂat mode

01 = min. mode

10 = min. mode

11= max. mode

7 selecting bit 0

Control register 1 1 and 0 serial I2S-bus input format 00 = I2S-bus

01 = 16-bit LSB justiﬁed

10 = 18-bit LSB justiﬁed

11= 20-bit LSB justiﬁed

3 and 2 digital PLL mode 00= adaptive

01 = ﬁx state 1

10 = ﬁx state 2

11= ﬁx state 3

select 00

4 digital PLL lock mode 0 = adaptive

1 = ﬁxed select 1

6 and 5 digital PLL lock speed 00 = lock after 512 samples

01 = lock after 2048 samples

10 = lock after 4096 samples

11= lock after 16348 samples

select 00

7 selecting bit 1