GENERAL DESCRIPTION

The ADF4368 is a high performance, ultra-low jitter, integer-N and

fractional-N phase-locked loop (PLL) with integrated VCO ideally

suited for frequency conversion applications.

The high performance PLL has a figure of merit of −239 dBc/Hz,

very low 1/f noise of normalized −287 dBc/Hz and high PFD

frequency that can achieve ultra-low in-band noise and integrated

jitter. The ADF4368 can generate any frequency from 800 MHz to

12.8 GHz without an internal doubler, which eliminates the need

for sub-harmonic filters. The Σ-Δ modulator includes a 25-bit fixed

modulus that allows hertz frequency resolution and an additional

17-bit variable modulus, which allows even finer resolution and

flexibility for frequency planning. The 9 dBm output power at 12.8

GHz in single-ended configuration with 16 step power adjust feature

makes it very useful for any application.

For multiple frequency conversion applications, such as phase

array radar or massive MIMO systems, the outputs of multiple

ADF4368 can be aligned by using the SYNC input or EZSync™.

The EZSync method is used when it is difficult to distribute the

SYNC signal to all devices precisely. For applications that require

deterministic delay or delay adjustment capability, a programmable

reference to output delay with <1 ps resolution is provided. The

reference to output delay is guaranteed across multiple devices

and temperature, allowing for predictable and precise multichip

alignment.

The simplicity of the ADF4368 block diagram eases development

time with a simplified serial-peripheral interface (SPI) register map,

external SYNC input, and repeatable multichip phase alignment

both in integer mode and fractional mode.

FEATURES

► Output frequency range: 800 MHz to 12.8 GHz

► Jitter < 30 fsRMS fOUT = 9.001 GHz, fREF = fPFD = 250 MHz,

fractional mode

► Wideband phase noise floor: −160 dBc/Hz at 12.8 GHz

► PLL specifications

► Normalized in-band phase noise floor

► −239 dBc/Hz: integer, −237 dBc/Hz: fractional mode

► Normalized 1/f phase noise floor

► −287 dBc/Hz: normalized to 1 Hz

► −147 dBc/Hz: normalized to 1 GHz at 10 kHz

► 625 MHz phase detector frequency integer mode

► 250 MHz phase detector frequency fractional mode

► 25-bit fixed, 49-bit combined fractional modulus

► 4 GHz reference input frequency

► Typical −95 dBc PFD spurs

► Reference to output delay specifications

► Temperature coefficient: 0.06 ps/°C

► Adjustment step size: <1 ps

► Multichip output phase alignment

► Through SYNC pin or by EZSync method

► 3.3 V and 5 V power supplies

► ADIsimPLL™ loop filter design tool support

► Available in 48-lead, 7 mm × 7 mm LGA package

► −40°C to +125°C operating junction temperature

APPLICATIONS

► Wireless infrastructure (MC-GSM, 5G)

► Test and measurement

► Aerospace and defense