GENERAL DESCRIPTION

The ADF4159 is a 13 GHz, fractional-N frequency synthesizer with modulation and both fast and slow waveform generation capability. The part uses a 25-bit fixed modulus, allowing subhertz

frequency resolution. The ADF4159 consists of a low noise digital phase frequency detector (PFD), a precision charge pump, and a programmable reference divider. The Σ-Δ-based fractional interpolator allows programmable fractional-N division. The INT and FRAC registers define an overall N divider as N = INT + (FRAC/225).

FEATURES

RF bandwidth to 13 GHz

High and low speed FMCW ramp generation

25-bit fixed modulus allows subhertz frequency resolution

PFD frequencies up to 110 MHz

Normalized phase noise floor of −224 dBc/Hz

FSK and PSK functions

Sawtooth, triangular, and parabolic waveform generation

Ramp superimposed with FSK

Ramp with 2 different sweep rates

Ramp delay, frequency readback, and interrupt functions

Programmable phase control

2.7 V to 3.45 V analog power supply

1.8 V digital power supply

Programmable charge pump currents

3-wire serial interface

Digital lock detect

ESD performance: 3000 V HBM, 1000 V CDM

APPLICATIONS

FMCW radars

Communications test equipment

Communications infrastructure