Resonance-coupled signaling between ic modules

Abstract

Coupled resonators for galvanically isolated signaling between integrated circuit modules. An illustrative system embodiment includes first and second integrated circuits. The first integrated circuit includes: a transmitter that produces a modulated carrier signal on a primary conductor; a first transfer conductor connected to a first connection terminal; and a first floating loop electromagnetically coupled to the primary conductor and to the transfer conductor to convey the modulated carrier. The second integrated circuit includes: a second transfer conductor connected to a second connection terminal, the second connection terminal being electrically connected to the first connection terminal; a receiver that demodulates the modulated carrier signal; and a second floating loop electromagnetically coupled to the second transfer conductor and to the receiver to convey the modulated carrier signal to the receiver. The first and second floating loops are each resonant at the carrier frequency to provide resonance-coupled signalling between the integrated circuits.

What is claimed is: 
     
         1 . A system for galvanically isolated signaling, comprising:
 a first integrated circuit including:
 a transmitter that modulates a carrier signal having a carrier frequency to produce a modulated carrier signal on a primary conductor; 
 a first transfer conductor connected to a first connection terminal; and 
 a first floating loop electromagnetically coupled to the primary conductor and electromagnetically coupled to the transfer conductor to convey the modulated carrier signal from the primary conductor to the transfer conductor, 
 wherein the first floating loop is resonant at the carrier frequency; and 
   a second integrated circuit including:
 a second transfer conductor connected to a second connection terminal, the second connection terminal being electrically connected to the first connection terminal; 
 a receiver that demodulates the modulated carrier signal; and 
 a second floating loop electromagnetically coupled to the second transfer conductor and electromagnetic coupled to the receiver to convey the modulated carrier signal from the second transfer conductor to the receiver, 
 wherein the second floating loop is resonant at the carrier frequency. 
   
     
     
         2 . The system of  claim 1 , wherein the first floating loop shares a common metallization layer with the primary conductor and the first transfer conductor, and wherein the second floating loop shares a common metallization layer with the second transfer conductor. 
     
     
         3 . The system of  claim 1 , wherein the first and second floating loops each include an integrated metal-insulator-metal plate capacitor. 
     
     
         4 . The system of  claim 1 , wherein the first and second transfer conductors are part of a closed, floating transfer loop. 
     
     
         5 . The system of  claim 4 , wherein the first connection terminal and the second connection terminal are coupled via a bond wire. 
     
     
         6 . The system of  claim 4 , wherein the transfer loop is not resonant at the carrier frequency. 
     
     
         7 . The system of  claim 1 , wherein the transmitter is configured to receive a digital signal and to responsively produce pulses in the modulated carrier signal. 
     
     
         8 . A method for galvanically isolated signaling, comprising:
 equipping a first integrated circuit with a transmitter that modulates a carrier signal having a carrier frequency to produce a modulated carrier signal on a primary conductor;   equipping a second integrated circuit with a receiver that demodulates the modulated carrier signal; and   electromagnetically coupling the transmitter to the receiver using a resonantly-coupled signal path having:
 a first floating loop that is resonant at the carrier frequency in the first integrated circuit; 
 a transfer loop that is not resonant at the carrier frequency; and 
 a second floating loop that is resonant at the carrier frequency in the second integrated circuit. 
   
     
     
         9 . The method of  claim 8 , wherein the transfer loop includes a first transfer conductor in the first integrated circuit, the first transfer conductor sharing a common metallization layer with the first floating loop, and wherein the transfer loop includes a second transfer conductor in the second integrated circuit, the second transfer conductor sharing a common metallization layer with the second floating loop. 
     
     
         10 . The method of  claim 9 , wherein the transfer loop further includes a first terminal connected to the first transfer conductor, a second terminal connected to the second transfer conductor, and a bond wire connecting the first terminal to the second terminal. 
     
     
         11 . The method of  claim 8 , further comprising providing an integrated capacitor in each of the first and second floating loops to make them each resonant at the carrier frequency. 
     
     
         12 . The method of  claim 11 , wherein the integrated capacitors are each metal-insulator-metal plate capacitors. 
     
     
         13 . The method of  claim 8 , wherein the transmitter is configured to receive a digital signal and to responsively produce pulses in the modulated carrier signal. 
     
     
         14 . An integrated circuit for galvanically isolated signaling via a connection terminal, the integrated circuit comprising:
 a transfer conductor connected to the connection terminal;   a transmitter that modulates a carrier signal having a carrier frequency to produce a modulated carrier signal; and   a floating loop electromagnetically coupled to the transmitter and to the transfer conductor to convey the modulated carrier signal from the transmitter to the transfer conductor,   wherein the floating loop is resonant at the carrier frequency.   
     
     
         15 . The integrated circuit of  claim 14 , wherein said connection terminal is a first connection terminal connected to a second connection terminal by the transfer conductor, the first and second connection terminals being configured for electrically connecting to a remote pair of connection terminals which in turn are electrically connected to form a floating transfer loop. 
     
     
         16 . The integrated circuit of  claim 15 , wherein the floating transfer loop is not resonant at the carrier frequency, and wherein the floating loop is configured to resonantly couple with a second floating loop via the transfer conductor, the second floating loop being resonant at the carrier frequency. 
     
     
         17 . The integrated circuit of  claim 15 , wherein each of said first and second connection terminals comprises a bonding pad on a first substrate, and wherein said remote pair of connection terminals comprises a pair of bonding pads on a second substrate. 
     
     
         18 . The integrated circuit of  claim 14 , wherein the transmitter is configured to receive a digital signal and to responsively produce pulses in the modulated carrier signal. 
     
     
         19 . The integrated circuit of  claim 14 , wherein the floating loop includes an integrated metal-insulator-metal plate capacitor.