ULN-2550 GPS Disciplined Oscillator

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 10 MHz, 25 MHz, 50 MHz, and/or 100 MHz sources. The 10 MHz and 100 MHz outputs are always available, while the 25 MHz output can be changed into a 50 MHz output via stuffing options. The ULN-2550 has the following main features: a high-end SC-cut Double Oven Crystal Oscillator, four 25/50 MHz LVDS outputs, one 100MHz CMOS output, as well as a 10 MHz CMOS output, a 1 PPS LVDS output, and a high-performance 50-channel GPS receiver with -160 dBm tracking capability. With the exception of the GPS antenna connection, the ULN-2550 provides all of its 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 25/50 MHz as well as 100 MHz and 10 MHz 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.

Highlights

• 10 MHz, 25 MHz/50 MHz, and 100 MHz outputs with 4x LVDS
• Typical Allan Deviations of <5E-11 with GPS lock for measurement intervals from 1 to 1000 s
• Phase noise of <125 dBc at >10 Hz offsets is standard
• Power consumption of <4 W with DOCXO at 25°C
• A high-end WAAS/EGNOS/MSAS GPS receiver drives an ultra-stable OCXO frequency reference under the control of a 32-bit Processor
• Hold-over mode with aging and temperature compensation
• Alarm outputs
• The unit can be controlled via RS-232 control using standard SCPI commands. Settings are automatically stored in non-volatile memory.
• Sine Wave, CMOS, and LVDS outputs
• GPSCon Windows graphing and SNTP server software compatible

Applications

• The ULN-2550 is a good fit for Ultra Low-Phase-Noise up-conversion systems as used in Radar and Satellite communication equipment.