PT8401 Datasheet, PDF (7/28 Pages) Princeton Technology Corp – MP3 Audio Decoder

Princeton Technology Corp.
MP3 Audio Decoder
Tel : [phone]
Fax: [phone]
URL: http://www.princeton.com.tw
PT8401
The default output waveform is show in Figure 4. Each PCM sample consists of a 2's complement
16-bit MSB-first data and another 16 bits of blank data forming 32 bits data in each channel.
ADQO is valid at the rising edge of ACKQO and the last bit of a sample is aligned with the edges of
ALRQO. However, PT8401 offers 3-bit, eight combinations to fit different kinds of audio DACs via
the start-up configuration or command registers.
Bit 0 : 32/16 bits per sample selection. If 16-bit per sample is selected, each channel contains only
16-bit MSB first data.
0
Left
1
Left
Right
Right
Bit 1 : ALRQO Left Channel indicating Low/High selection.
Bit 2 : Delay Selection. When this bit is set, the transition of ALRQO is one clock cycle earlier.
This is called I²S format.
ALRQO
Left Channel
Right Channel
0
1514131211 4 3 2 1 0
ADQO
1
15141312 5 4 3 2 1 0
1514131211 4 3 2 1 0
15141312 5 4 3 2 1 0
FIRST SERIAL BITSTREAM INPUT INTERFACE
Serial Bitstream (regardless of whether it is an MPEG audio or ADPCM speech bitstream) comes from
this port. The following three signals are needed to make a complete transfer.
BD1: Serial Bitstream Data Input.
BCK1: Bit Clock Input.
B_ENA1: Serial Data Enable Signal, Active: Low
DATA_REQ : Data Request Signal.
PT8401 v 1.3
Page 7
Updated March 2002