CS8420 datasheet(55/80 Pages) CIRRUS

55 / 80 page

CS8420

DS245PP2

Audio Output Interface:

SDOUT - Serial Audio Output Port Data Output

Audio data serial output pin. This is also a start-up option pin, and requires a pull-up or pull-down

resistor.

OSCLK - Serial Audio Output Port Bit Clock Input or Output

Serial bit clock for audio data on the SDOUT pin.

OLRCK - Serial Audio Output Port Left/Right Clock Input or Output

Word rate clock for the audio data on the SDOUT pin. The frequency will be at the output sample rate

(Fso).

AES3/SPDIF Transmitter Interface:

TXN, TXP - Differential Line Driver Outputs

Differential line driver outputs, transmitting AES3 type data. Drivers are pulled to low while the CS8420

is in the reset state.

TCBL - Transmit Channel Status Block Start

When operated as output, TCBL is high during the first sub-frame of a transmitted channel status block,

and low at all other times. When operated as input, driving TCBL high for at least three OMCK clocks

will cause the current transmitted sub-frame to be the start of a channel status block.

CUVEN - C, U and V bit Input Enable Mode Input

The CUVEN pin determines how the channel status data, user data and validity bit is input. When

CUVEN is low, hardware mode 2A is selected, where the EMPH/V, COPY/C and ORIG/U pins are used

to enter selected channel status data. When CUVEN is high, hardware 2B is selected, where the

EMPH/V, COPY/C and ORIG/U pins are used to enter serial C, U and V data.

EMPH/V - Pre-emphasis Indicator Input or V bit Input

In mode 2A EMPH/V low sets the 3 EMPH channel status bits to indicate 50/15

µs pre-emphasis.

EMPH/V high sets the 3 EMPH bits to 000 indicating no pre-emphasis. In mode 2B EMPH/V low sets

the V bit to indicate valid audio. EMPH/V high sets the V-bit to indicate non-valid audio.

COPY/C - COPY Channel Status bit Input or C bit Input

In mode 2A, the COPY/C pin determines the state of the COPY, PRO and L Channel Status bits in the

outgoing AES3 type data stream (See Table 7). In mode 2B, COPY/C becomes the direct C bit input

data pin.

ORIG/U - ORIG Channel Status bit Input or U bit Input

In mode 2A, the ORIG/U pin determines the state of the COPY, PRO and L Channel Status bits in the

outgoing AES3 type data stream. (See Table 7). In mode 2B, ORIG/U becomes the direct U bit input

data pin.

CS8420 Datasheet(PDF) 55 Page - Cirrus Logic