Epson and Rohde & Schwarz, announced their joint development of a modern test procedure for measuring power supply noise rejection to bring clarity and precision to real-world signal integrity design challenges. The companies will introduce and demonstrate the procedure and summarized data from Epson’s SG3225EEN low noise differential crystal oscillator measured by the R&S FSWP phase noise analyzer from Rohde & Schwarz at DesignCon 2020 being held in Santa Clara, Calif. from Jan. 28-30.

Jitter negatively impacts the bit error rate in a digital communication system. Component manufacturers generally only measure an oscillator's jitter under suitable conditions for product specifications. When applied to actual systems, jitter is often higher than the specified components' jitter due to noise sources such as power supply noise that are intentionally minimized in a laboratory environment. The lack of specifications related to external sources makes it difficult to select the best oscillator from a datasheet. Epson and Rohde & Schwarz’s paper proposes measurement techniques to quantify power supply noise's contribution to jitter using commonly available test and measurement equipment.

“Epson is committed to manufacturing differentiated products that bring value to customers,” said Masaru Sato, director of marketing and sales, Microdevices, Epson America, Inc. “Epson is excited to share our expertise with the design and signal integrity community alongside Rohde & Schwarz at DesignCon and beyond. Working with Rohde & Schwarz allows us to provide customers the tools needed to design, prototype and manufacture next-generation solutions.”

Epson’s SG3225EEN crystal oscillator delivers sub-100 femtosecond phase jitter performance to enable the low bit error rates required for ever-increasing data rates in today’s networking equipment. The combination of low phase noise, small form factor and exceptional power supply noise rejection (PSNR) helps solve signal integrity challenges in real-world systems deployed in today’s networks.

The R&S FSWP phase noise analyzer and VCO tester offers phase noise and amplitude noise measurements, based on a digital demodulation concept. With its phase noise sensitivity, it is the instrument of choice for measuring ultra-low jitter devices like oscillators, clocks and phase-locked loops (PLLs). Artificial power supply noise is generated and measured with the R&S RTO2000 oscilloscope. With its built-in function and arbitrary waveform generator and the dedicated power rail probes, sinusoidal power supply noise with a defined amplitude is injected to the power rails of the oscillator. The power supply induced phase noise and jitter is measured by the R&S FSWP, demonstrating the PSNR performance of the SG3225EEN crystal oscillator.

Sebastian Richter, Vice President Market Segment Industry, Components, Research & Universities at Rohde & Schwarz, says, “Rohde & Schwarz always strives to create innovative test solutions that are characterized by a high measurement performance, compact setup and user-friendly operation. We are excited to collaborate with Epson and together present this measurement technique to the whole industry.”

The joint presentation, “Testing Power Supply Noise Rejection in Differential Oscillators,” by Epson and Rohde & Schwarz will be held on Wednesday, Jan. 29 at 3:45 p.m. in the Chiphead Theater during DesignCon.