Texas Instruments Corporation

Ganesh Kiran

Visvesvaraya Appala Pentakota

Jagannathan Venkataraman

Nagarajan Viswanathan

Viswanathan Nagarajan

In pipeline analog-to-digital converters (ADCs) the third harmonic can degrade the performance of the ADC, and conventional circuits that attempt to cancel this third harmonic are oftentimes sensitive to process variation, temperature variation, and common mode variations. Here a correction circuit is provided that includes a compensator that adjusts control voltages for MOS capacitors to generally ensures that the difference between the gate-source voltages and threshold voltages of MOS capacitors is generally maintained across variations of process, temperature, and common mode.

Non-linearity correction that is independent of input common mode, temperature variation, and process variation

Multiplying digital-to-analog converters (MDACs), which are generally employed in pipelined analog-to-digital converters (ADCs), can have a settling error associated with the MDAC amplifier. Here, a circuit is provided that includes additional amplifiers and a capacitor network that compensates for this settling error. Thus, a more accurate pipelined ADC can now be produced.

Apparatus for correcting setting error in an MDAC amplifier

Improving signal-to-noise ratio (SNR) when using fewer bits than the number of output bits of an ADC as digital representation of the strength of the samples of an input signal. In an embodiment, an ADC generates digital values of H bits by sampling an input signal at corresponding time instances. An error signal representing the (H-N) least significant bits of the H-bit digital values is processed to determine respective filtered values, which are respectively added to the corresponding ones of the H-bit digital values. The (H-N) bits of the resulting added values are dropped to generate N bit values. The N bit values thus generated may have improved SNR at least in a band of interest, as desired.

Growing community of inventors

Bengaluru, India

Ganesh Kiran