The Next Generation of Timing & Frequency


The ULN-2550 time-, frequency-, and position-reference is an extremely small Global Positioning System Disciplined Oscillator (GPSDO) optimized for up-conversion applications that require 100MHz, 25MHz, 10MHz, and/or 50MHz sources. The 10MHz and 100MHz outputs are always available, while the 25MHz output can be changed into a 50MHz output via stuffing options. The ULN-2550 has the following main features: a high-end SC-cut Double Oven Crystal Oscillator, four 25/50MHz LVDS outputs, one 100MHz CMOS output, as well as a10MHz CMOS output, a 1PPS LVDS output, and a high-performance 50-channel GPS receiver with -160dBm tracking capability. With the exception of the GPS antenna connection, the ULN-2550 provides all of it's IO and power-input on one single connector that can either have a board-to-board interface, or a cable harness, making system integration straight forward, and compatible to stringent military requirements.

All outputs are frequency and phase-synchronized to UTC via the GPS system, and thus provide Better-Than-Cesium™ long-term performance. By providing 25/50MHz as well as 100MHz and 10MHz references in one compact board, the unit is a good fit for Ultra Low-Phase-Noise up-conversion systems as used in Radar and Satellite communication equipment.

ULN-2550 OCXO options

The ULN-2550 can be ordered with the following options depending on the stability/cost requirements:
  • Single oven option, for a very effective cost/performance ratio.
  • Double OCXO, standard operating temperature (−25°C to +75°C), for higher stability and better holdover performance.
  • Double OCXO, extended operating temperature (−40°C to +85°C), for highest stability and best holdover performance.