RF Stimulus Used to Synchronize a Clock Network

Abstract

CMOS LC tank circuits and flux linkage between inductors can be used to distribute and propagate clock signals over the surface of a VLSI chip or μprocessor. A structure is placed close to the surface of the IC. This structure contains circuitry to generate RF signals. These signals can originate from individual inductors, cavity oscillators, antennas, or other forms of RF signal generation. These signals are applied to the surface of the IC and are detected by the coils of an LC tank circuit formed in the metallization. These signals are used to force each of the LC tank circuits into synchronism. In addition, the inductance of the LC tank circuit can comprise several inductors coupled in parallel. Thus, the external signal provides the stimulus to synchronize individual LC tank circuits located in the IC.

1 . An apparatus comprising: 
 an RF structure that generates a first stimulus;    an IC substrate; and,    a first tank circuit comprising a plurality of inductors coupled in parallel; wherein, 
 the first LC tank circuit is formed on the IC substrate; and,  
 at least one of the plurality of inductors is flux linked to the first stimulus.  
   
     
     
         2 . The apparatus of  claim 1 , further comprising: 
 a regenerative circuit coupled to the first LC tank circuit.    
     
     
         3 . The apparatus of  claim 1 , wherein: 
 the first stimulus can synchronize the first LC tank circuit.    
     
     
         4 . The apparatus of  claim 1 , wherein: 
 the first stimulus is carried by a magnetic field coupling formed between the RF structure and the IC substrate.    
     
     
         5 . The apparatus of  claim 1 , wherein: 
 the first stimulus can be generated by circuit oscillators, cavity oscillators, or antennae that are formed on the RF structure.    
     
     
         6 . The apparatus of  claim 1 , wherein: 
 each of the plurality of inductors are placed in a separate inductor layout area of the IC substrate.    
     
     
         7 . The apparatus of  claim 1 , further comprising: 
 at least one additional stimulus; and,    at least one additional LC tank circuit; wherein, 
 a regenerative circuit is coupled to each LC tank circuit.  
   
     
     
         8 . The apparatus of  claim 7 , wherein: 
 each additional stimulus can synchronize each additional LC tank circuit.    
     
     
         9 . The apparatus of  claim 7 , wherein: 
 each additional LC tank circuit is placed in a separate LC tank circuit layout area of the IC substrate.    
     
     
         10 . The apparatus of  claim 7 , wherein: 
 the first and additional stimulus are independent of each another.    
     
     
         11 . A RF signal generation unit, comprising: 
 an RF structure having a planar surface;    a plurality of RF generation signal circuits placed across the planar surface; and,    a plurality of stimuli that emanates from the planar surface; wherein, 
 each of the plurality of RF signal generation circuits generates one of the plurality of stimuli; and,  
 at least one of the plurality of stimuli is applied to an external LC tank circuit.  
   
     
     
         12 . The unit of  claim 11 , further comprising: 
 a regenerative circuit coupled to the external LC tank circuit.    
     
     
         13 . The unit of  claim 11 , wherein: 
 the external LC tank circuit is formed on an IC substrate.    
     
     
         14 . The unit of  claim 11 , wherein: 
 the RF structure is magnetically coupled to the external LC tank circuit.    
     
     
         15 . The unit of  claim 11 , further comprising: 
 at least one additional external LC tank circuit; wherein, 
 each one of the remaining plurality of stimuli is applied to each additional external LC tank circuit.  
   
     
     
         16 . The unit of  claim 15 , wherein: 
 the external LC tank circuits are formed on an IC substrate.    
     
     
         17 . The unit of  claim 16 , wherein: 
 the RF structure is positioned juxtaposed to the IC substrate.    
     
     
         18 . The unit of  claim 16 , wherein: 
 the external LC tank circuits are placed in separate layout areas of the IC substrate.    
     
     
         19 . The unit of  claim 11 , wherein: 
 the RF generation signal circuits are formed using inductors, cavity oscillators, or antennae.    
     
     
         20 . The unit of  claim 11 , wherein: 
 the external LC tank circuit comprises tow or more inductors coupled in parallel.    
     
     
         21 . The unit of  claim 20 , wherein: 
 one of the plurality of stimuli is magnetically coupled to at least one inductor in the external LC tank circuit.    
     
     
         22 . A substrate unit, comprising: 
 a planar surface; and,    a plurality of LC tank circuits; wherein, 
 at least one LC tank circuit comprises: 
 a plurality of inductors coupled in parallel; wherein, 
 at least one inductor from the plurality of inductors intercepts an external stimulus.  
 
 
   
     
     
         23 . The unit of  claim 22 , wherein: 
 the plurality of inductors from at least one of the plurality of LC tank circuits are formed on the planar surface.    
     
     
         24 . The unit of  claim 22 , wherein: 
 the plurality of inductors from at least one LC tank circuit occupy non-overlapping regions of the planar surface.    
     
     
         25 . The unit of  claim 22 , wherein: 
 the plurality of LC tank circuits are formed on the planar surface and occupy non-overlapping regions of the planar surface.    
     
     
         26 . The unit of  claim 25 , wherein: 
 at least one of the plurality of LC tank circuits is synchronized by the external stimulus.    
     
     
         27 . A method of synchronizing an LC tank circuit, comprising the steps of: 
 forming an RF structure that generates a stimulus which is applied to an IC substrate;    creating the LC tank circuit which has two or more inductors coupled in parallel;    placing the LC tank circuit on the IC substrate;    positioning the RF structure juxtaposed to the IC substrate to flux link the stimulus to at least one of the inductors; and,    synchronizing the LC tank circuit.    
     
     
         28 . An apparatus, comprising: 
 a first unit that generates a stimulus;    a second unit comprising at least one LC tank circuit;    the LC tank circuit comprising a plurality of inductors that are coupled in parallel; and,    the stimulus from the first unit is magnetically coupled to at least one inductor in the LC tank circuit.    
     
     
         29 . The apparatus of  claim 28 , wherein: 
 the LC tank circuit is synchronized by the stimulus.