Wireless Systems Design

Oscillator Delivers High Stability In Small Package

In a crystal oscillator, ambient temperature variation is one of the main causes of frequency variation. To overcome such variation, C-MAC's TC-OCXOs use a hybrid combination of limited temperature control by use of an oven. They further reduce the remaining frequency error through the use of the company's Pluto temperature-compensation ASIC. The company's new series of temperature-compensated, oven-controlled crystal oscillators (TC-OCXOs) also is designed to deliver the high stability of an OCXO from a device with low power consumption, small size, and light weight. Because they're capable of stabilities better than ±0.05 ppm over operating-temperature range, these TC-OCXOs will initially be aimed at mobile, battery-powered, and remote applications like GPS, satellite communications, distress beacons, and secure radio.

C-MAC's TC-OCXO approach uses a miniature oven with crude temperature control to keep the crystal oscillator at an approximately constant temperature. That temperature is slightly above its specified operating-temperature range. The result is an oscillator with overall stability that is nearly an order of magnitude better than the most stable TCXOs (comparable to that of an OCXO). Yet the oscillator will have better power consumption, smaller and lighter package size, and faster warm-up. For example, a typical specification might offer the following: ±0.05 ppm stability over a temperature range of −20° to +70°C at standard frequencies from 5 to 20 MHz; a highly linear ±5-ppm frequency adjustment for aging effects; power consumption of 400 mW or less at −20°C steady state (or 1.0 mW or less during warm-up) from a 3.3-V supply; and a 20.7-×-13.08-mm DIL package.

For information on pricing, please contact the company.

C-MAC MicroTechnology
Antell House, Windsor Place, Harlow, Essex, CM20 2GQ, United Kingdom; +44 (0)1279 774465, FAX: +44 (0)1279 774488, www.cmac.com.

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.