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