Acoustic wave resonator with integrated temperature control for oscillator purposes

Abstract

The present invention relates to a resonator structure, temperature compensation method and temperature control apparatus for controlling local temperature of a resonator structure. At least one heating element ( 55 ) is integrated on a substrate of the resonator structure, and a temperature control signal generated based on a stored temperature characteristic is applied to the at least one integrated heating element ( 55 ). Thereby, the at least one heating element ( 55 ) and an optional integrated sensing element can be provided very close to the resonator. It is thus possible to control or calibrate variations of sensing elements, heating elements and resonator out from every sample.

1 . A temperature control apparatus for controlling local temperature of a resonator structure, said apparatus comprising:
 a) a memory for storing information about a temperature characteristic of said resonator structure; and   b) a control for generating a temperature control signal based on said stored information, and for applying said control signal to an integrated heating element of said resonator structure.   
   
   
       2 . An apparatus according to  claim 1 , wherein said control is adapted to read values of sampling points at a predetermined timing, and to update said stored information using said read values. 
   
   
       3 . A method of compensating temperature variations in a resonator structure, said method comprising:
 a) integrating at least one heating element on a substrate of said resonator structure,   b) applying a temperature control signal to said at least one integrated heating element to obtain a temperature characteristic, and   c) storing said temperature characteristic of said resonator structure.   
   
   
       4 . A method according to  claim 3 , further comprising deriving said temperature characteristic from sampling points measured during manufacture of said resonator structure. 
   
   
       5 . A method according to  claim 4 , further comprising integrating a temperature sensing element on said substrate, and using a sensed temperature value obtained from said temperature sensing element to update said stored temperature characteristic at a predetermined timing.