Title:
【発明の名称】結晶発振器用の温度補償回路
Document Type and Number:
Japanese Patent JP2001527707
Kind Code:
A
Abstract:
A temperature compensation circuit (10) for a crystal oscillator module (12) used in a communication device (200). An existing microcontroller (210) of the communication device (200) is used to provide temperature compensating digital data (30) for a crystal oscillator (18). In this way, the crystal oscillator module (12) does not require an on-board memory which substantially cuts costs. The temperature compensation digital data (30) is converted to a temperature compensation signal (22) in a digital-to-analog converter which controls the crystal oscillator frequency. However, typical digital-to-analog converters are driven by voltage regulators which vary over temperature. To solve this problem, the crystal oscillator module (12) includes an on-board voltage regulator (34) which supplies a characterized regulated voltage (36) to the digital-to-analog converter such that the temperature compensation signal (22) from the digital-to-analog converter is inherently corrected for voltage variations in the voltage regulator (34). This improves stability of the output frequency (20) from about 5 ppm to about 2 ppm.
Inventors:
Sturiff, Richard N
Raza, Side S
Lorich, Mathias F
Telemac, Vladimir
Raza, Side S
Lorich, Mathias F
Telemac, Vladimir
Application Number:
JP52767798A
Publication Date:
December 25, 2001
Filing Date:
October 15, 1997
Export Citation:
Assignee:
CTS CORPORATION
International Classes:
H03B5/32; H03B5/04; H03B5/36; H03J7/12; H03L1/02; H04B1/40; H03B1/00; (IPC1-7): H03L1/02; H03B5/04; H03B5/32
Attorney, Agent or Firm:
Takehiko Suzue (4 outside)