Systems and methods mitigating temperature dependence of circuitry in electronic devices

Abstract

Methods and systems for compensating for temperature variation in the performance of electronic circuits and systems are disclosed. In some embodiments, the systems are configured to store compensation parameters determined in calibration, where the compensation parameters are used by the systems to modify performance. In some embodiments, the systems are part of an automatic test equipment (ATE) system.

What is claimed is: 
     
         1 - 16 . (canceled) 
     
     
         17 . An electronic device, comprising:
 a circuit, comprising:
 a signal input configured to receive a controllably variable input signal, 
 a reference input unit configured to receive a reference signal, and 
 an output unit configured to generate a variable output signal corresponding to the input signal, wherein the correspondence of the output signal to the input signal is dependent at least in part on a temperature, and wherein the dependence of the correspondence on the temperature is based at least in part on the reference signal, such that a change in the correspondence in response to a change in the temperature is based partly on the reference signal; 
   a reference signal generator, comprising:
 an input unit configured to receive a control input, and 
 an output unit configured to generate the reference signal for the circuit, wherein the reference signal is dependent at least in part on the temperature, and wherein the temperature dependence of the reference signal is based at least in part on the control input; and 
   a programmable register, configured to generate the control input of the reference signal generator based on a programmed register value, wherein the programmed register value is determined based on a plurality of measurements of the output signal at a plurality of temperatures and at a plurality of control inputs.   
     
     
         18 . The device of  claim 17 , wherein the programmed register value minimizes the change in the correspondence in response to a change in the temperature. 
     
     
         19 . The device of  claim 17 , wherein the input unit of the reference signal generator comprises a programmable current source. 
     
     
         20 . The device of  claim 17 , wherein the output unit of the reference signal generator comprises a current to voltage converter. 
     
     
         21 . The device of  claim 17 , wherein the reference generator comprises a bandgap voltage reference generator. 
     
     
         22 . The device of  claim 17 , wherein the output signal comprises a controlled voltage. 
     
     
         23 . The device of  claim 17 , wherein the output signal comprises a controlled current. 
     
     
         24 . The device of  claim 17 , wherein the output signal comprises a controlled propagation delay. 
     
     
         25 . A method of programming an electronic device, the device comprising a circuit and a programmable reference signal generator, wherein the reference signal generator is configured to generate a reference signal based at least in part on a programmable code value and on a temperature, and wherein the circuit is configured to generate a variable output signal corresponding to the input signal, wherein the correspondence of the output signal to the input signal is dependent at least in part on a temperature, and wherein the dependence of the correspondence on the temperature is based at least in part on the reference signal, such that a change in the correspondence in response to a change in the temperature is based partly on the reference signal, the method comprising:
 programming the reference signal generator with each of multiple code values;   setting the temperature to each of multiple temperature values;   measuring a value of the variable output signal for each of a plurality of combinations of the multiple code values and the multiple temperature values;   selecting a programming code value based on the measured variable output signal values; and   programming the reference signal generator with the selected programming code value.   
     
     
         26 . The method of  claim 25 , wherein the dependence of the correspondence on the temperature is based at least in part on the programming code value, wherein the programming code value is selected from a plurality of code values each corresponding to one of a plurality of temperature dependences of the correspondence, and wherein the selected programming code value corresponds with a minimum temperature dependence. 
     
     
         27 . The method of  claim 25 , wherein setting the temperature comprises at least one of:
 heating the electronic device in an oven;   cooling the electronic device in a cooler;   operating the electronic device in a power mode corresponding to the temperature to be set;   sensing a temperature of the device; and   adjusting the temperature based on the sensed temperature.   
     
     
         28 . The method of  claim 25 , wherein the measuring comprises:
 recording a first output signal value for a first programmed code value and a first temperature value,   recording a second output signal value for the first programmed code value and a second temperature value,   recording a third output signal value for a second programmed code value and the first temperature value, and   recording a fourth output signal value for the second programmed code value and the second temperature value.   
     
     
         29 . The method of  claim 28 , wherein the selecting comprises:
 determining a first correspondence temperature dependence for the first programmed code value based on the first and second recorded output signal values;   determining a second correspondence temperature dependence for the second programmed code value based on the third and fourth recorded output signal values; and   calculating a relationship between programmable code values and temperature dependence of the correspondence based on the first and second output signal temperature dependences,   wherein selecting the programming code value comprises selecting the code value corresponding to a minimum temperature dependence of the correspondence based on the relationship.   
     
     
         30 . The method of  claim 25 , wherein the measuring comprises:
 recording a first output signal value for a first programmed code value, a first input value, and a first temperature value,   recording a second output signal value for the first programmed code value, the first input value, and a second temperature value,   recording a third output signal value for the first programmed code value, a second input value, and the first temperature value,   recording a fourth output signal value for the first programmed code value, the second input value, and the second temperature value,   recording a fifth output signal value for a second programmed code value, the first input value, and the first temperature value,   recording a sixth output signal value for the second programmed code value, the first input value, and the second temperature value,   recording a seventh output signal value for the second programmed code value, the second input value, and the first temperature value, and   recording an eighth output signal value for the second programmed code value, the second input value, and the second temperature value,   and wherein the selecting comprises:
 determining a first correspondence temperature dependence for the first programmed code value based on the first, second, third, and fourth, recorded output signal values, 
 determining a second correspondence temperature dependence for the second programmed code value based on the fifth, sixth, seventh, and eighth recorded output signal values, and 
 calculating a relationship between programmable code values and temperature dependence of the correspondence based on the first and second parameter temperature dependences, 
   wherein selecting the programming code value comprises selecting the code value corresponding to a minimum temperature dependence of the correspondence based on the relationship.   
     
     
         31 . The method of  claim 30 , wherein:
 determining the first correspondence temperature dependence comprises averaging a temperature dependence determined based on the first and second recorded output signal values and a temperature dependence determined based on the third and fourth recorded output signal values; and   determining the second correspondence temperature dependence comprises averaging a temperature dependence determined based on the fifth and sixth recorded output signal values and a temperature dependence determined based on the seventh and eighth recorded output signal values.   
     
     
         32 . The method of  claim 25 , wherein programming the reference signal generator with each of multiple code values comprises programming a programmable register, and programming the reference signal generator with the selected programming code value comprises programming the programmable register. 
     
     
         33 . The method of  claim 32 , wherein the reference signal generator comprises a programmable current source, configured to source a current dependent on the code value programmed in the programmable register. 
     
     
         34 . The method of  claim 32 , wherein the reference signal generator comprises a current to voltage converter, configured to source a voltage dependent on the code value programmed in the programmable register. 
     
     
         35 . The method of  claim 25 , wherein the reference signal generator comprises a bandgap voltage reference generator. 
     
     
         36 . The method of  claim 25 , wherein measuring the value of the output signal comprises measuring an output voltage generated by the circuit. 
     
     
         37 . The method of  claim 25 , wherein measuring the value of the output signal comprises measuring an output current generated by the circuit. 
     
     
         38 . The method of  claim 25 , wherein measuring the value of the output signal comprises measuring a propagation delay generated by the circuit.