GENERAL DESCRIPTION
The UDA1325 is a single chip stereo USB codec incorporating bitstream converters designed for implementation in USB-compliant audio peripherals and multimedia audio applications. It contains a USB interface, an embedded microcontroller, an Analog-to-Digital Interface (ADIF) and an Asynchronous Digital-to-Analog Converter (ADAC).

FEATURES
General
• High Quality USB-compliant Audio/HID device
• Supports 12 Mbits/s serial data transmission
• Fully USB Plug and Play operation
• Supports ‘Bus-powered’ and ‘Self-powered’ operation
• 3.3 V power supply
• Low power consumption with optional efficient power control
• On-chip clock oscillator, only an external crystal is required.

Audio playback channel
• One isochronous output endpoint
• Supports multiple audio data formats (8, 16 and 24 bits)
• Adaptive sample frequency support from 5 to 55 kHz
• One master 20-bit I2S digital stereo playback output, I2S and LSB justified serial formats
• One slave 20-bit I2S digital stereo playback input, I2S and LSB justified serial formats
• Selectable volume control for left and right channel
• Soft mute control
• Digital bass and treble tone control
• Selectable on-chip digital de-emphasis
• Low total harmonic distortion (typical 90 dB)
• High signal-to-noise ratio (typical 95 dB)
• One stereo Line output.

Audio recording channel
• One isochronous input endpoint
• Supports multiple audio data formats (8, 16 and 24 bits)
• Twelve selectable sample rates (4, 8, 16 or 32 kHz; 5.5125, 11.025, 22.05 or 44.1 kHz; 6, 12, 24 or 48 kHz) via analog PLL (APLL).
• Selectable sample rate between 5 to 55 kHz via a second oscillator (optional)
• One slave 20-bit I2S digital stereo recording input, I2S and LSB justified serial formats
• Programmable Gain Amplifier for left and right channel
• Low total harmonic distortion (typical 85 dB)
• High signal-to-noise ratio (typical 90 dB)
• One stereo Line/Microphone input.

USB endpoints
• 2 control endpoints
• 2 interrupt endpoints
• 1 isochronous data sink endpoint
• 1 isochronous data source endpoint.

Document references
• “USB Specification”
• “USB Device Class Definition for Audio Devices”
• “Device Class Definition for Human Interface Devices (HID)”
• “USB HID Usage Table”.
• “USB Common Class Specification”.

APPLICATIONS
• USB monitors
• USB speakers
• USB microphones
• USB headsets
• USB telephone/answering machines
• USB links in consumer audio devices.