ADF4378 Microwave Wideband Synthesizer with Integrated VCO

Analog Devices ADF4378 is a high-performance, ultra-low jitter, integer-N phased locked loop (PLL) with an integrated voltage-controlled oscillator (VCO) and system reference (SYSREF) retimer ideally suited for data converter and mixed-signal front end (MxFE) clock applications. The high-performance PLL has a -239 dBc/Hz for normalized in-band phase noise floor, ultra-low 1/f noise, and a high phase/frequency detector (PFD) frequency that can achieve ultra-low in-band noise and integrated jitter. The fundamental VCO and output divider of the ADF4378 generate frequencies from 800 MHz to 12.8 GHz. The ADF4378 integrates all necessary power-supply bypass capacitors, which saves board space on compact boards.

For multiple data converter and MxFE clock applications, the ADF4378 simplifies clock alignment and calibration routines required with other clock solutions by implementing the automatic reference to output synchronization feature, the matched reference to output delays across process, voltage, and temperature feature, and the less than ±0.1 ps, jitterf-ree reference to output delay adjustment capability feature.

The general-purpose pulse retimer feature allows for predictable and precise multichip clock and pulse alignment for SYSREF, SYNC, and multichip synchronization (MCS) architectures. JESD204B and JESD204C Subclass 1 solutions are supported by pairing the ADF4378 with an integrated circuit (IC) that distributes pairs of reference and SYSREF signals. The pulse retimer feature simplifies the system design by allowing the widely distributed SYSREF to only meet the slower reference frequency timing versus the much more stringent output clock timing. Serial peripheral interface (SPI) selectable current-mode logic (CML)/low-voltage positive/pseudo-emitter-coupled logic (LVPECL) or low-voltage differential signaling (LVDS) SYSREF input and LVDS SYSREF output allow CML to LVDS signal conversion, which simplifies clock and SYSREF alignment for various converters. The pulse retimer feature also can be used with transceiver MCS signals and SYNC signals for other ICs.

The EV-ADF4378SD1Z evaluates the performance of the ADF4378 frequency synthesizer with an integrated voltage-controlled oscillator (VCO) for phase-locked loops (PLLs), a USB interface, power supply connectors, on-board reference oscillator, propagation delay calibration paths, and Subminiature Version A (SMA) connectors. The outputs are AC-coupled with 50 Ω transmission lines, which make the outputs suitable to drive 50 Ω impedance instruments. The EV-ADF4378SD1Z requires an SDP-S board (not supplied with the kit). The SDP-S allows software programming of the EV-ADF4378SD1Z with ACE software.