GENERAL DESCRIPTION

The AD9854 digital synthesizer is a highly integrated device that uses advanced DDS technology, coupled with two internal high speed, high performance quadrature DACs to form a digitally programmable I and Q synthesizer function. When referenced to an accurate clock source, the AD9854 generates highly stable, frequency-phase, amplitude-programmable sine and cosine outputs that can be used as an agile LO in communications, radar, and many other applications. The innovative high speed DDS core of the AD9854 provides 48-bit frequency resolution (1 μHz tuning resolution with 300 MHz SYSCLK). Maintaining 17 bits ensures excellent SFDR.

FEATURES

300 MHz internal clock rate

FSK, BPSK, PSK, chirp, AM operation

Dual integrated 12-bit digital-to-analog converters (DACs)

Ultrahigh speed comparator, 3 ps rms jitter

Excellent dynamic performance 80 dB SFDR at 100 MHz (±1 MHz) AOUT

4× to 20× programmable reference clock multiplier

Dual 48-bit programmable frequency registers

Dual 14-bit programmable phase offset registers

12-bit programmable amplitude modulation and on/off output shaped keying function

Single-pin FSK and BPSK data interfaces

PSK capability via input/output interface

Linear or nonlinear FM chirp functions with single-pin frequency hold function

Frequency-ramped FSK

<25 ps rms total jitter in clock generator mode

Automatic bidirectional frequency sweeping

Sin(x)/x correction

Simplified control interfaces

10 MHz serial 2- or 3-wire SPI compatible

100 MHz parallel 8-bit programming

3.3 V single supply

Multiple power-down functions

Single-ended or differential input reference clock

Small, 80-lead LQFP or TQFP with exposed pad

APPLICATIONS

Agile, quadrature LO frequency synthesis

Programmable clock generators

FM chirp source for radar and scanning systems

Test and measurement equipment

Commercial and amateur RF exciters