Diversity in magnetic sensors

Abstract

A magnetic angle sensor including a first Wheatstone bridge circuit having a plurality of first magnetoresistive elements; and a second Wheatstone bridge circuit having a plurality of second magnetoresistive elements, wherein the plurality of second magnetoresistive elements have diversity with respect to the plurality of first magnetoresistive elements.

1 - 5 . (canceled) 
     
     
         6 . A magnetic sensor, comprising:
 a first sensor chip; and   a second sensor chip stacked vertically on the first sensor chip within a same package.   
     
     
         7 . The magnetic sensor of  claim 6 , wherein the first and second sensor chips are coupled by wire bonding. 
     
     
         8 . The magnetic sensor of  claim 6 , wherein the first and second sensor chips are coupled by metallic balls using a flip-chip method. 
     
     
         9 . A magnetic sensor, comprising:
 a first sensor stack; and   a second sensor stack based on a different sensor technology that the first sensor stack.   
     
     
         10 . The magnetic sensor of  claim 9 , further comprising:
 an isolating dielectric layer located between the first sensor stack and the second sensor stack, and   wherein the second sensor stack is stacked on the first sensor stack monolithically.   
     
     
         11 . The magnetic sensor of  claim 10 , wherein the first sensor stack is based on one of a giant magnetoresistance (GMR) and a tunnel magnetoresistance (TMR) technology, and the second sensor stack is based on the other of the GMR and TMR technology, and each of the first and second sensor stacks is configured to operate in a current-in-plane (CIP) configuration. 
     
     
         12 . The magnetic sensor of  claim 10 , wherein the first sensor is based on one of a giant magnetoresistance (GMR) and a tunnel magnetoresistance (TMR) technology, and the second sensor stack is based on an anisotropic magnetoresistive (AMR) technology, and each of the first and second sensor stacks is configured to operate in a current-in-plane (CIP) configuration. 
     
     
         13 . The magnetic sensor of  claim 10 , wherein the first sensor stack is based on one of a giant magnetoresistance (GMR) and a tunnel magnetoresistance (TMR) technology and is configured to operate in current-in-plane (CIP) configuration, and the second sensor stack is a TMR technology and is configured to operate in a current perpendicular-to-plane (CPP) configuration. 
     
     
         14 . The magnetic sensor of  claim 10 , wherein each of the first and second sensor stacks is based on a tunnel magnetoresistance (TMR) technology and comprises:
 a bottom electrode;   a top electrode;   a non-magnetic layer located between the bottom and top electrodes; and   first and second terminals coupled to the top electrode,   wherein when the first and second terminals are configured to operate in a current-in-plane (CIP) configuration, the top electrode exhibits anisotropic magnetoresistive (AMR) effect.   
     
     
         15 . The magnetic sensor of  claim 10 , wherein each of the first and second sensor stacks is based on a tunnel magnetoresistance (TMR) technology and comprises:
 a bottom electrode;   a top electrode;   a non-magnetic layer located between the bottom and top electrodes;   first and second terminals coupled to the top electrode; and   third and fourth terminals coupled to the bottom electrode,   wherein when the first and second terminals are coupled to a supply voltage, and the third and fourth terminals are coupled to a ground voltage, the TMR sensor is configured to operate in a current perpendicular-to-plane (CPP) configuration for a TMR effect.   
     
     
         16 - 17 . (canceled) 
     
     
         18 . A magnetic sensor, comprising:
 a first Wheatstone bridge circuit;   a second Wheatstone bridge circuit; and   a control circuit coupled to each of the first and second Wheatstone bridge circuits, and comprising an even number of magnetoresistive elements, wherein each magnetoresistive element has a fixed reference magnetization direction that is opposite a fixed reference magnetization direction of one of the other magnetoresistive elements,   wherein the control circuit is configured to output a constant control voltage independent of an applied magnetic field direction unless the magnetic sensor is experiencing a malfunction.   
     
     
         19 . The magnetic sensor of  claim 18 , wherein the control circuit comprises:
 a first control circuit comprising:
 first and second magnetoresistive elements having opposing fixed reference magnetization directions and coupled in series with a first branch of the first Wheatstone bridge; 
 a first control output coupled at a node between the first and second magnetoresistive elements and the first branch of the first Wheatstone bridge; 
 third and fourth magnetoresistive elements having opposing fixed reference magnetization directions and coupled in series with a second branch of the first Wheatstone bridge; and 
 a second control output coupled at a node between the third and fourth magnetoresistive elements and the second branch of the first Wheatstone bridge; and 
   a second control circuit comprising:
 fifth and sixth magnetoresistive elements having opposing fixed reference magnetization directions and coupled in series with a first branch of the second Wheatstone bridge; 
 a third control output coupled at a node between the fifth and sixth magnetoresistive elements and the first branch of the second Wheatstone bridge; 
 seventh and eighth magnetoresistive elements having opposing fixed reference magnetization directions and coupled in series with a second branch of the second Wheatstone bridge; and 
 a fourth control output coupled at a node between the seventh and eighth magnetoresistive elements and the second branch of the second Wheatstone bridge, 
   wherein the first, second, third, and fourth control outputs are configured to output constant control voltages independent of an applied magnetic field direction unless the magnetic sensor is experiencing a malfunction.   
     
     
         20 . The magnetic sensor of  claim 18 , wherein:
 the control circuit is comprised within the first and second Wheatstone bridge circuits,   a first branch of the first Wheatstone circuit is coupled in series with a first branch of the second Wheatstone circuit, and a second branch of the first Wheatstone circuit is coupled in series with a second branch of the second Wheatstone circuit,   the first Wheatstone bridge circuit has an orientation that is one quarter of a period different from the orientation of the second Wheatstone bridge circuit,   the first branch of the first Wheatstone circuit comprises first and second magnetoresistive elements having opposing fixed reference magnetization directions,   the first branch of the second Wheatstone circuit comprises third and fourth magnetoresistive elements having opposing fixed reference magnetization directions,   the second branch of the first Wheatstone circuit comprises fifth and sixth magnetoresistive elements having opposing fixed reference magnetization directions, and   the second branch of the second Wheatstone circuit comprises seventh and eighth magnetoresistive elements having opposing fixed reference magnetization directions, and   the control circuit comprises:
 a first control output coupled at a node between the first branch of the first Wheatstone circuit and the first branch of the second Wheatstone circuit, and 
 a second control output coupled at a node between the second branch of the first Wheatstone circuit and the second branch of the second Wheatstone circuit, and 
   the first and second control outputs are configured to output constant control voltages independent of an applied magnetic field direction unless the magnetic sensor is experiencing a malfunction.   
     
     
         21 . A magnetic sensor channel, comprising:
 the magnetic sensor of  claim 20 ;   a first power supply configured to supply the first branch of the first Wheatstone bridge circuit and the first branch of the second Wheatstone bridge circuit;   a second power supply configured to supply the second branch of the first Wheatstone bridge circuit and the second branch of the second Wheatstone bridge circuit;   a first amplifier configured to amplify an output of the first branch of the first Wheatstone bridge circuit;   a second amplifier configured to amplify an output of the first branch of the second Wheatstone bridge circuit;   a third amplifier configured to amplify an output of the second branch of the first Wheatstone bridge circuit; and   a fourth amplifier configured to amplify an output of the second branch of the second Wheatstone bridge circuit.   
     
     
         22 . A magnetic sensor channel, comprising:
 the magnetic sensor of  claim 18 ,   a first power supply configured to supply a first branch of the first Wheatstone bridge circuit and a first branch of the second Wheatstone bridge circuit;   a second power supply configured to supply a second branch of the first Wheatstone bridge circuit and a second branch of the second Wheatstone bridge circuit;   a first amplifier configured to amplify an output of the first branch of the first Wheatstone bridge circuit;   a second amplifier configured to amplify an output of the first branch of the second Wheatstone bridge circuit;   a third amplifier configured to amplify an output of the second branch of the first Wheatstone bridge circuit; and   a fourth amplifier configured to amplify an output of the second branch of the second Wheatstone bridge circuit.   
     
     
         23 . The magnetic sensor of  claim 18 ,
 wherein the first Wheatstone bridge circuit comprises first and second branches,   wherein the second Wheatstone bridge circuit comprises first and second branches, and   wherein the magnetic sensor further comprises respective amplifiers configured to amplify respective output signals of the first and second branches of the first and second Wheatstone bridge circuits.   
     
     
         24 . The magnetic sensor of  claim 18 ,
 wherein a first branch of the first Wheatstone circuit is coupled in series with a first branch of the second Wheatstone circuit, and a second branch of the first Wheatstone circuit is coupled in series with a second branch of the second Wheatstone circuit, and   wherein the magnetic sensor further comprises:
 a first power supply configured to supply a first branch of the first Wheatstone bridge circuit and a first branch of the second Wheatstone bridge circuit; and 
 a second power supply configured to supply a second branch of the first Wheatstone bridge circuit and a second branch of the second Wheatstone bridge circuit.