GENERAL DESCRIPTION

The AD9953 is a direct digital synthesizer (DDS) featuring a 14-bit DAC operating up to 400 MSPS. The AD9953 uses advanced DDS technology, coupled with an internal high speed, high performance DAC to form a digitally programmable, complete high frequency synthesizer capable of generating a frequency-agile analog output sinusoidal waveform at up to 200 MHz. The AD9953 includes an integrated 1024 × 32 static RAM to support flexible frequency sweep capability in several modes. The AD9953 is designed to provide fast frequency hopping and fine tuning resolution (32-bit frequency tuning word). The frequency tuning and control words are loaded into the AD9953 via a serial I/O port.

The AD9953 is specified to operate over the extended industrial temperature range of –40°C to +105°C.

FEATURES

400 MSPS internal clock speed

Integrated 14-bit DAC

32-bit tuning word

Phase noise ≤ –120 dBc/Hz @ 1 kHz offset (DAC output)

Excellent dynamic performance

>80 dB SFDR @ 160 MHz (±100 kHz offset) AOUT

Serial I/O control

1.8 V power supply

Software and hardware controlled power-down

48-lead TQFP/EP package

Support for 5 V input levels on most digital inputs

PLL REFCLK multiplier (4× to 20×)

Internal oscillator, can be driven by a single crystal

Phase modulation capability

Multichip synchronization

APPLICATIONS

Agile VHF/UHF LO frequency synthesis

FM chirp source for radar and scanning systems

Nonlinear-shaped PSK/FSK modulator

Test and measurement equipment