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