Method and circuit for switching a memristive device

Abstract

A method of switching a memristive device applies a current ramp of a selected polarity to the memristive device. The resistance of the device during the current ramp is monitored. When the resistance of the memristive device reaches the target value, the current ramp is removed.

1 .- 15 . (canceled) 
     
     
         16 . A method of switching a memristive device, comprising:
 applying a first current ramp of a first polarity to the memristive device simultaneously and in parallel to a reference resistor of a first target value;   monitoring a resistance of the memristive device during the first current ramp; and   turning the first current ramp off when the resistance of the memristive device reaches the first target value.   
     
     
         17 . A method as in  claim 16 , wherein the step of monitoring includes comparing a voltage across the memristive device with a voltage across the reference resistor. 
     
     
         18 . A method as in  claim 17 , wherein the step of comparing includes feeding the voltage across the memristive device and the voltage across the reference resistor to a latched comparator. 
     
     
         19 . A method as in  claim 17 , wherein the steps of applying the current ramp to the memristive device and the reference resistor include driving a current mirror with the current ramp and feeding output currents of the current mirror to the memristive device and the reference resistor. 
     
     
         20 . A method as in  claim 16 , further including:
 applying a second current ramp to the memristive device;   monitoring the resistance of the memristive device during the second current ramp;   removing the second current ramp from the memristive device when the resistance of the memristive device reaches a second resistance value.   
     
     
         21 . A method as in  claim 20 , wherein the first current ramp is non-linear. 
     
     
         22 . A method as in  claim 20 , wherein the second current ramp is of a second polarity opposite to the first polarity. 
     
     
         23 . A switching circuit for switching a memristive device, comprising:
 a current driver component for passing a current ramp simultaneously and in parallel through the memristive device and a reference resistor of a target value;   a control component for monitoring a resistance of the memristive device and removing the current ramp from the memristive device when the resistance of the memristive device reaches the target value by turning the current ramp off.   
     
     
         24 . A switching circuit as in  claim 23 , wherein the current driver component includes a current mirror. 
     
     
         25 . A switching circuit as in  claim 24 , wherein the control component includes a reference resistor connected to the current mirror such that output current of the current mirror duplicating the current ramp passes through the reference resistor. 
     
     
         26 . A switching circuit as in  claim 25 , wherein the control component further includes a latched comparator connected to take a voltage of the memristive device and a voltage of the reference resistor as inputs. 
     
     
         27 . A switching circuit as in  claim 26 , wherein the current ramp is non-linear. 
     
     
         28 . A switching system for switching a memristive device, comprising:
 a first half and a second half connected by the memristive device to form an H-bridge, the first half including a first current driver component and a first control component, and the second half including a second current driver component and a second control component,   wherein the first current driver component passes a first current ramp through the memristive device in a first direction, the first control component turns the first current ramp off when a resistance of the memristive device reaches a first target value, the second current driver component passes a second current ramp through the memristive device in a second direction opposite to the first direction, and the second control component turns the second current ramp off when the resistance of the memristive device reaches a second target value.   
     
     
         29 . A switching circuit as in  claim 28 , wherein the first half includes a first reference resistor for providing the first target value, and the second half includes a second reference resistor for providing the second target value. 
     
     
         30 . A switching circuit as in  claim 29 , wherein the first and second current driver components each includes a current mirror.