Systems and methods for providing compact digitally controlled trim of multi-segment circuits
AssigneeLinear Technology Corporation
InventorJames Lee Brubaker
Life of this patent
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Abstract
A trimdac circuit for adjusting the output of a digital-to-analog converter (DAC) is provided. The trimdac may be used, to adjust a plurality of resistor segments in the DAC. The trimdac may include a programmable Read Only Memory (ROM) or other suitable memory device. The ROM may include a plurality of multi-bit digital words. Each of the multi-bit digital words may control a plurality, and most preferably a pair of variable resistance circuits. Each of the pair of variable resistance circuits may adjust a resistor segment of the DAC,
Claims34
A trimdac circuit for adjusting the output of a digital-to-analog converter (DAC) by adjusting a plurality of resistor segments in the DAC, the circuit comprising a programmable Read Only Memory (ROM), the ROM comprising a plurality of multi-bit digital words, each of the multi-bit digital words that controls a plurality of adjustable impedance structures, each of the plurality of structures that adjusts a resistor segment in the DAC.
A method of improving the linearity of the output of a digital-to-analog converter (DAC) the method, comprising:
- determining a non-linearity of the DAC;
- generating a multi-bit digital word in response to the determination of the non-linearity of the DAC;
- and
- using the multi-bit digital word to adjust at least two adjustable impedance structures, each of the adjustable impedance structures that adjusts a resistor segment in the DAC.
A digital to analog converter (DAC) comprising:
- a trimdac circuit for adjusting the output of the DAC, the trimdac circuit comprising:
- a programmable Head-Only-Memory (ROM), the ROM comprising a plurality of multi-bit digital words, each of the digital words that controls a plurality of variable resistance circuits, each of the variable resistance structures that, adjusts a resistor segment in the DAC.
A method of adjusting an electronic circuit, said method obtaining a substantially uniform effect across a range of operation of said electronic circuit, said electronic circuit comprising a plurality of elements, said method comprising:
- adjusting a first element of said plurality of elements, said adjusting obtaining a disproportional effect on the output of the electronic circuit across the range of operation of the electronic circuit;
- adjusting a second element of said plurality of elements, said adjusting the second element obtaining a disproportional effect on the output of the electronic circuit across the range of operation of the electronic circuit;
- and
- wherein the combination of adjusting the first element and adjusting the second element obtains an effect across the range of the output of the electronic circuit that is more uniformly distributed than the effect obtained by adjusting one of the first element and the second element.
An electronic circuit comprising a substantially uniform transfer function across a range of operation of said electronic circuit, said electronic circuit comprising a plurality of elements, said circuit comprising:
- a first element of said plurality of elements, the adjustment of said first element that obtains a disproportional effect on the output of the electronic circuit across the range of operation of the electronic circuit;
- a second element of said plurality of elements, the adjustment, of the second element that obtains a disproportional effect on the output of the electronic circuit across the range of operation of the electronic circuit;
- and
- a trim circuit that adjusts the first element and the second element, the combination of adjusting the first element and adjusting the second element that obtains an effect, across the range of the output of the electronic circuit that is more uniformly distributed than the effect obtained by adjusting one of the first element and the second element.
Dependencies are inferred from the claim text.