Temperature compensation circuit

A temperature compensation circuit, comprising:

• a first temperature dependent signal generator having a first activation temperature, said first temperature dependent signal generator being effective for producing a first signal proportional to temperature when temperature is not lower than said first activation temperature and for producing substantially no signal when temperature is below said first activation temperature;
• a second temperature dependent signal generator, said second temperature dependent signal generator being effective for producing a second signal inversely proportional to temperature when temperature is not lower than a second activation temperature;
• a first summing node for summing said first signal and said second signal and outputting the result on a first summation output node;
• wherein said first temperature dependent signal generator includes:
• a first signal source for producing a first sub-signal inversely proportional to temperature;
• a second signal source for producing a second sub-signal directly proportional to temperature;
• and
• a second summing node for subtracting the magnitude of said first sub-signal from the magnitude of said second sub-signal;
• wherein for temperatures lower than a predefined transition temperature the magnitude of said first sub-signal is not less than the magnitude of said second sub-signal, and for temperatures not lower than said predefined transition temperature the magnitude of said first sub-signal is less than the magnitude of said second sub-signal.

A temperature compensation circuit, comprising:

• a first temperature dependent signal generator having a first activation temperature, said first temperature dependent signal generator being effective for producing a first signal proportional to temperature when temperature is not lower than said first activation temperature and for producing substantially no signal when temperature is below said first activation temperature;
• a second temperature dependent signal generator, said second temperature dependent signal generator being effective for producing a second signal inversely proportional to temperature when temperature is not lower than a second activation temperature;
• a first summing node for summing said first signal and said second signal and outputting the result on a first summation output node;
• wherein said first signal and said second signal are voltage signals, and wherein said first summation node is a summing amplifier having a first summing input coupled to receive said first signal and a second summing input coupled to receive said second signal.

A temperature compensation circuit comprising:

• a first temperature dependent signal generator having a first activation temperature, said first temperature dependent signal generator being effective for producing a first signal proportional to temperature when temperature is not lower than said first activation temperature and for producing substantially no signal when temperature is below said first activation temperature;
• a second temperature dependent signal generator, said second temperature dependent signal generator being effective for producing a second signal inversely proportional to temperature when temperature is not lower than a second activation temperature;
• a first summing node for summing said first signal and said second signal and outputting the result on a first summation output node;
• wherein said second temperature dependent signal generator further includes:
• a third sub-signal source;
• and
• a second dependent signal generator for generating a second weighted signal dependent on the output from said third sub-signal source.

A temperature compensation circuit, comprising:

• a first temperature dependent signal generator having a first activation temperature, said first temperature dependent signal generator being effective for producing a first signal proportional to temperature when temperature is not lower than said first activation temperature and for producing substantially no signal when temperature is below said first activation temperature;
• a second temperature dependent signal generator, said second temperature dependent signal generator being effective for producing a second signal inversely proportional to temperature when temperature is not lower than a second activation temperature;
• a first summing node for summing said first signal and said second signal and outputting the result on a first summation output node;
• further comprising:
• a transimpedance amplifier having an input coupled to said first summation node;
• a voltage controlled oscillator responsive to said transimpedance amplifier.

A temperature compensation circuit, comprising:

• a first temperature dependent current signal generator having a first activation temperature, said first temperature dependent current signal generator being effective for producing a first current signal proportional to temperature when temperature is not lower than said first activation temperature and for producing substantially no signal when temperature is below said first activation temperature;
• a second temperature dependent current signal generator, said second temperature dependent signal generator being effective for producing a second current signal inversely proportional to temperature;
• a first summing node for summing said first current signal and said second current signal and outputting the result on a first summation output node;
• wherein said first temperature dependent current signal generator includes:
• a first current source inversely proportional to temperature;
• and
• a first current sink directly proportional to temperature;
• and
• a second summing node having a first lead coupled to said current source and a second lead coupled to said current sink;
• wherein for temperatures lower than a predefined transition temperature the magnitude of the output current of said first current source is not less than the magnitude of the sinking current of said current sink, and for temperatures not lower than said predefined transition temperature the magnitude the output current of said current source is less than the magnitude of the sinking current of said current sink.

A temperature compensation circuit, comprising:

• a first temperature dependent current signal generator having a first activation temperature, said first temperature dependent current signal generator being effective for producing a first current signal proportional to temperature when temperature is not lower than said first activation temperature and for producing substantially no signal when temperature is below said first activation temperature;
• a second temperature dependent current signal generator, said second temperature dependent signal generator being effective for producing a second current signal inversely proportional to temperature;
• a first summing node for summing said first current signal and said second current signal and outputting the result on a first summation output node;
• wherein said second temperature dependent signal generator further includes:
• a sub-signal source;
• and
• a second dependent current source for generating a second weighted signal dependent on the output from said sub-signal source.

A temperature compensated oscillator comprising:

• a temperature compensation circuit;
• and
• a variable frequency oscillator responsive to the output of said first summation node;
• wherein
• said temperature compensation circuit comprises:
• a first temperature dependent current signal generator having a first activation temperature, said first temperature dependent current signal generator being effective for producing a first current signal proportional to temperature when temperature is not lower than said first activation temperature and for producing substantially no signal when temperature is below said first activation temperature;
• a second temperature dependent current signal generator, said second temperature dependent signal generator being effective for producing a second current signal inversely proportional to temperature;
• a first summing node for summing said first current signal and said second current signal and outputting the result on a first summation output node.