Analog Devices,inc.

Daniel Rey-Losada

Franklin Marshall Murden, Ii

Corey Petersen

Daniel F Kelly

A common mode feedback (CMFB) loop for a differential amplifier sense an output common mode of a differential circuit and provides feedback to the gates of tail current transistors. Many CMFB loops cannot easily adjust the output common mode voltage and the output common mode may vary over process, voltage, and temperature. An improved CMFB circuit adds a control circuit to control backgates of tail current transistor device(s) of the differential circuit such that the output common mode voltage can be made adjustable.

Common mode feedback circuit with backgate control

In an example, a differential amplifier is disclosed that is configured to realize low noise with decreased overall system current. The differential amplifier may include a first amplifier stage and a second amplifier stage arranged in series, wherein a pull-up current iflowing as a single bias current i=iflows into the first stage. A single pull-down current isources to ground from the second stage, wherein i=i=isubstantially. In certain embodiments, the transconductance of the second stage may be increased by providing two transconductors coupled at their base nodes.

Reduced-power dissipation for circuits handling differential pseudo-differential signals

An amplifier with a single-input class-AB output stage comprises an input stage providing a signal to an output stage. The output stage comprises a current-splitting stage having a bias current and providing at least two intermediate output currents, and a drive stage receiving the two intermediate output currents and driving an output signal having a positive side and a negative side.

Single input class-AB rail-to-rail output stage

A bias voltage source for a differential circuit has low output impedance at DC, but considerably higher output impedance within the frequency band of the differential signal being processed, to provide an accurate, well-matched common-mode bias voltage to each component of a differential signal path, while providing a low noise current, minimizing the conversion between common-mode and differential modes, and preserving available headroom, and all without requiring the use of large resistors.

Common mode bias circuit

A system for correcting programming failures in an M-bit primary array of programmable fuses. The address of the failed fuse is stored in a secondary fuse array. Correction logic coupled to the primary and secondary arrays propagates the programming states of the good fuses, and corrects the programming state of the failed fuse, if any. The correction logic preferably comprises a decoder coupled to the secondary array which produces a one-hot M-bit word representing the failed fuse, and combinatorial logic arranged to receive the programming states of the primary array fuses and the one-hot M-bit word at respective inputs and to produce the correction logic output. Multiple failures can be accommodated using multiple secondary arrays, each storing the address of a respective failed fuse, or a tertiary array which stores the address of a failed fuse in either the primary or secondary arrays.

System and method for correcting programming failures in a programmable fuse array

A system for digitizing the magnitude of a first parameter, which can be inferred by applying to a second parameter and digitizing the magnitude of a resulting third parameter. The circuit which applies the second parameter has an associated bias point with which the magnitude of the second parameter varies. The value of the first parameter can result in an error in the value of the second parameter which results in an error being incurred when the digitized value of the third magnitude is used to infer a digitized value of the magnitude of the first parameter. This is avoided by adjusting the bias point with each successive trial and employing a sequential-trial ADC which performs sequential comparisons between the third magnitude and respective decision thresholds, such that there is no error in the magnitude of the second parameter when the third magnitude is equal to the decision threshold for a particular trial.

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San Diego, CA, United States of America

Daniel Rey-Losada