ESD protection circuit for high speed signaling including T/R switches

Abstract

An ESD protection circuit for a transistor having a drain and source coupled to high-speed signaling pins of an integrated circuit includes a first string of clamping elements and a second string of clamping elements. The first string of clamping elements has a collective capacitance less than the capacitance of a single clamping element. The first string of clamping elements is operably coupled to the drain and source of the transistor and conducts when a first polarity ESD voltage is applied to the high-speed pins. The second string of clamping elements has a collective capacitance less than the capacitance of one clamping element. The second string of clamping elements is operably coupled to the drain and source of the transistor and conducts when a second polarity ESD voltage is applied to the high speed signaling pins.

1 . An electro-static discharge (ESD) protection circuit for a transistor having a drain and a source coupled to high-speed signal pins of an integrated circuit, the ESD protection circuit comprises: 
 a first string of clamping elements having a collective capacitance less than capacitance of one clamping element of the first string of clamping elements, wherein the first string of clamping elements is operably coupled to the drain and the source of the transistor and to conduct when a first polarity ESD voltage is applied to the high-speed signal pins; and    a second string of clamping elements having a collective capacitance less than capacitance of one clamping element of the second string of clamping elements, wherein the second string of clamping elements is operably coupled to the drain and the source of the transistor and to conduct when a second polarity ESD voltage is applied to the high-speed signal pins.    
   
   
       2 . The ESD protection circuit of  claim 1 , wherein each clamping element of the first and second strings of clamping elements further comprises at least one of: a diode and a transistor.  
   
   
       3 . The ESD protection circuit of  claim 1 , wherein at least one clamping element of the first string of clamping elements further comprises at least one of: a diode and a transistor.  
   
   
       4 . The ESD protection circuit of  claim 1 , wherein at least one clamping element of the second string of clamping elements further comprises at least one of: a diode and a transistor.  
   
   
       5 . An electro-static discharge (ESD) protection circuit for a transistor having a gate, a drain, and a source coupled to high-speed signal pins of an integrated circuit, the ESD protection circuit comprises: 
 a first string of clamping elements having a collective capacitance less than capacitance of one clamping element of the first string of clamping elements, wherein the first string of clamping elements is operably coupled to the drain and the gate of the transistor and to activate the transistor when a first polarity ESD voltage is applied to the high-speed signal pins; and    a second string of clamping elements having a collective capacitance less than capacitance of one clamping element of the second string of clamping elements, wherein the second string of clamping elements is operably coupled to the gate and the source of the transistor and to activate the transistor when a second polarity ESD voltage is applied to the high-speed signal pins.    
   
   
       6 . The ESD protection circuit of  claim 5 , wherein each clamping element of the first and second strings of clamping elements further comprises at least one of: a diode and a transistor.  
   
   
       7 . The ESD protection circuit of  claim 5 , wherein at least one clamping element of the first string of clamping elements further comprises at least one of: a diode and a transistor.  
   
   
       8 . The ESD protection circuit of  claim 5 , wherein at least one clamping element of the second string of clamping elements further comprises at least one of: a diode and a transistor.