PRODUCT OVERVIEW
The AD1890 and AD1891 SamplePorts™ are fully digital, stereo Asynchronous Sample Rate Converters (ASRCs) that solve sample rate interfacing and compatibility problems in digital audio equipment. Conceptually, these converters interpolate the input data up to a very high internal sample rate with a time resolution of 300 ps, then decimate down to the desired output sample rate. The AD1890 is intended for 18- and 20-bit professional applications, and the AD1891 is intended for 16-bit lower cost applications where large dynamic sample-rate changes are not encountered.

FEATURES
    Automatically Sense Sample Frequencies—No Programming Required
    Tolerant of Sample Clock Jitter
    Smooth Transition When Sample Clock Frequencies Cross
    Accommodate Dynamically Changing Asynchronous Sample Clocks
    8 kHz to 56 kHz Sample Clock Frequency Range
    1:2 to 2:1 Ratio Between Sample Clocks
    –106 dB THD+N at 1 kHz (AD1890)
    120 dB Dynamic Range (AD1890)
    Optimal Clock Tracking Control
        –Short/Long Group Delay Modes
        –Slow/Fast Settling Modes
    Linear Phase in All Modes
    Equivalent of 4 Million 22-Bit FIR Filter Coefficients Stored On-Chip
    Automatic Output Mute
    Flexible Four Wire Serial Interfaces
    Low Power

APPLICATIONS
    Digital Mixing Consoles and Digital Audio Workstations
    CD-R, DAT, DCC and MD Recorders
    Multitrack Digital Audio and Video Tape Recorders
    Studio to Transmitter Links
    Digital Audio Signal Routers/Switches
    Digital Audio Broadcast Equipment
    High Quality D/A Converters
    Digital Tape Recorder Varispeed Applications
    Computer Communication and Multimedia Systems