1FEATURES
23· PCM2904: Without S/PDIF
· PCM2906: With S/PDIF
· On-Chip USB Interface:
– With Full-Speed Transceivers
– Fully Compliant With USB 1.1 Specification
– Certified by USB-IF
– Partially Programmable Descriptors (1)
– USB Adaptive Mode for Playback
– USB Asynchronous Mode for Record
– Bus Powered
· 16-Bit Delta-Sigma ADC and DAC
· Sampling Rate:
– DAC: 32, 44.1, 48 kHz
– ADC: 8, 11.025, 16, 22.05, 32, 44.1, 48 kHz
· On-Chip Clock Generator With Single 12-MHz
Clock Source
· Single Power Supply: 5 V Typical (VBUS)
· Stereo ADC
– Analog Performance at VBUS = 5 V
– THD+N = 0.01%
– SNR = 89 dB
– Dynamic Range = 89 dB
– Decimation Digital Filter
– Pass-Band Ripple = ±0.05 dB
– Stop-Band Attenuation = –65 dB
– Single-Ended Voltage Input
– Antialiasing Filter Included
– Digital LCF Included
· Stereo DAC:
– Analog Performance at VBUS = 5 V
– THD+N = 0.005%
– SNR = 96 dB
– Dynamic Range = 93 dB
– Oversampling Digital Filter
– Pass-Band Ripple = ±0.1 dB
– Stop-Band Attenuation = –43 dB
– Single-Ended Voltage Output
– Analog LPF Included
· Multifunctions:
– Human Interface Device (HID) Volume ±
Control and Mute Control
– Suspend Flag
· Package: 28-Pin SSOP

APPLICATIONS
· USB Audio Speaker
· USB Headset
· USB Monitor
· USB Audio Interface Box

DESCRIPTION
The PCM2904/2906 is Texas Instruments single-chip
USB stereo audio codec with USB-compliant
full-speed protocol controller and S/PDIF (PCM2906
only). The USB protocol controller works with no
software code, but the USB descriptors can be
modified in some areas (for example, vendor
ID/product ID). The PCM2904/2906 employs SpAct™
architecture, TI's unique system that recovers the audio clock from USB packet data. On-chip analog
PLLs with SpAct enable playback and record with low
clock jitter and with independent playback and record
sampling rates.