Datasheet

www.ti.com
INTERFACE SEQUENCE
Power-On, Attach, and Play Back Sequence
D+(pin 4),
D–(pin 3)
V
OUT
L (pin 18),
V
OUT
R (pin 22)
2.5 V (typ.)
0 V
700 µs
Internalreset
Readyforsetup
Devicesetup
1staudiodata
SOF
2ndaudiodata
1 ms
Readyforplayback
SSPND(pin 29)
Busreset
Setconfiguration
SOF SOF
BusIdle
5.0 V
(typ.)
BPZ
V (pin2)
BUS
PCM2912
SLES216 – FEBRUARY 2008
The PCM2912 is ready for setup when the reset sequence has finished and the USB bus is attached. After a
connection has been established by setup, the PCM2912 is ready to accept USB audio data. While awaiting the
audio data (idle state), the analog output is set to bipolar zero (BPZ).
When receiving the audio data, the PCM2912 stores the first audio packet, which contained 1-ms audio data, into
the internal storage buffer. The PCM2912 starts playing the audio data when detecting the following Start of
Frame (SOF) packet.
Figure 33. Initial Sequence
Copyright © 2008, Texas Instruments Incorporated Submit Documentation Feedback 23
Product Folder Link(s): PCM2912