V

DD

2.7 V

Min. 100 ns

Reset

RST

Operation

Unknown

DIR9001

Status

DIR9001

SLES198A – DECEMBER 2006 – REVISED MAY 2015

www.ti.com

8.3 Feature Description

8.3.1 Acceptable Biphase Input Signal and Biphase Input Pin (RXIN)

The DIR9001 can decode the biphase signal format which is specified in one of the following standards.

Generally, these following standards may be called Sony/Philips digital interface format (S/PDIF) or AES/EBU.

•

IEC60958 (revised edition of former IEC958)

•

JEITA CPR-1205 (revised edition of former EIAJ CP-1201, CP-340)

•

AES3

•

EBU tech3250

The sampling frequency range and data word length which DIR9001 can decode is as follows:

•

Sampling frequency range is 28 kHz to 108 kHz.

•

Maximum audio sample word length is 24-bit.

Note of others about the biphase input signal.

•

The capture ratio of the built-in PLL complies with level III of sampling frequency accuracy (±12.5%), which is

specified in IEC60958-3.

•

The jitter tolerance of the DIR9001 complies with IEC60958-3.

•

The PLL may also lock in outside of the specified sampling-frequency range, but extended range is not

assured.

Notice about the signal level and transmission line of the biphase input signal.

•

The signal level and the transmission line (optical, differential, single-ended) are different in each standard.

•

The biphase input signal is connected to the RXIN pin of the DIR9001.

•

The RXIN pin has a 5-V tolerant TTL-level input.

•

An optical receiver module (optical to electric converter) such as TOSLINK, which is generally used in

consumer applications, is connected directly to the RXIN pin without added external components.

•

The output waveform of the optical receiver module varies depending on the characteristics of each product

type, so a dumping resistor or buffer amplifier might be required between the optical receiver module output

and the DIR9001 input. Careful handling is required if the optical receiver module and the DIR9001 are

separated by a long distance.

•

The DIR9001 needs an external amplifier if it is connected to a coaxial transmission line.

•

The DIR9001 needs an external differential to single-ended converter, attenuator, etc., for general consumer

applications if non-optical transmission line is used.

8.3.2 System Reset

The DIR9001 reset function is controlled by and external reset pin, RST.

The reset operation must be performed during the power-up sequence as shown in Figure 4. Specifically, the

DIR9001 requires reset operation with a 100-ns period after the supply voltage rises above 2.7 V.

Figure 4. Required System Reset Timing

12

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