Analog devices’ low jitter synthesiser enables excellent performance in GSPS data converter solutions

The new ADF4377 synthesiser enables signal-to-noise performance by providing a clean clock source to drive the signal sampling process. This allows next-gen wideband receivers and transmitters to utilise higher levels of dynamic range, which leads to greater receiver sensitivity and transmitter spectral purity. The performance is achieved by the ADF4377 synthesiser delivering jitter levels below 18fs rms because of the low normalised in-band phase noise at -239dBc/Hz, -147dBc/Hz normalised 1/f noise and a wideband voltage control oscillator (VCO) noise floor of -160dBc/Hz.   

The ADF4377 synthesiser is suitable for applications such as radar, instrumentation, and wideband receivers requiring multiple data converters or mixed-signal front-end (MxFE) digitisers to operate together. The ADF4377 significantly simplifies the alignment and calibration routines by allowing groups of data converters to sample their signals in alignment with each other.

This is fundamental to the operation of next-gen ultra-wideband multi-channel systems and is achieved by implementing:

• Automatic reference to output synchronisation.
• Well-matched reference to output delays across process (3ps part to part), voltage and temperature (0.03ps/C). 
• Sub-ps, jitter-free reference to output delay adjustment capability (+/- 0.1ps).

These features allow for predictable and precise multi-chip clock and SYSREF alignment. JESD204B and JESD204C subclass 1 solutions are supported by pairing the ADF4377 synthesiser with an IC that distributes pairs of reference and SYSREF signals. The ADF4377 integrates all necessary power supply bypass capacitors, saving board space on compact boards.

ADF377 Key Features:

• Output frequency range: 800MHz to 12.8GHz
• Jitter = 18fs rms (Integration BW: 100Hz to 100MHz)
• Wideband Noise Floor: -160dBc/Hz @12GHz
• PLL Specifications:
• -239dBc/Hz: Normalised In-Band Phase Noise Floor
• -147dBc/Hz: Normalised In-Band 1/f Noise
• Phase Detector Frequency up to 500 MHz
• Reference to Output Delay Specifications:
• Part-to-Part Standard Deviation: 3ps
• Temperature Drift: 0.03ps/℃
• Multi-chip Output Phase Alignment