Texas Instruments Corporation

Himanshu Varshney

Nagarajan Viswanathan

Charls Babu

Visvesvaraya Appala Pentakota

Neeraj Shrivastava

Vinam Arora

Srinivas Kumar Naru

Jawaharlal Tangudu

Shagun Dusad

Eeshan Miglani

Pankaj Gupta

Sreenath Narayanan Potty

Viswanathan Nagarajan

Rajendrakumar Joish

Narasimhan Rajagopal

Chandrasekhar Sriram

Ajai Paulose

Sai Aditya Nurani

Jafar Sadique Kaviladath

Raju Kharataram Chaudhari

Supreet Joshi

Divyeshkumar Mahendrabhai Patel

Parth Sameer Kalgaonkar

Mishab I

Mahesh Ravi Varma

Shabbar Abbasi Vejlani

An example analog-to-digital converter (ADC) includes first ADC circuitry, second ADC circuitry, and dither circuitry. The dither circuitry of the example ADC is to generate a first dither signal to produce a first dithered input signal at a first output coupled to an input of the first ADC circuitry, generate a second dither signal to produce a second dithered input signal at a second output coupled to an input of the second ADC circuitry, the first dither signal and the second dither signal to have opposite signs, and produce an output signal at a third output based on the first output of the first ADC circuitry and the second output of the second ADC circuitry.

Dithering techniques for analog-to-digital converters

In an example, a system includes an input channel and a voltage to delay converter (V2D) coupled to the input channel. The system also includes a first multiplexer coupled to the V2D and an analog-to-digital converter (ADC) coupled to the first multiplexer. The system includes a second multiplexer coupled to the input channel and an auxiliary ADC coupled to the second multiplexer. The system includes calibration circuitry coupled to an output of the auxiliary ADC, where the calibration circuitry is configured to correct a non-linearity in a signal provided by the input channel. The calibration circuitry is also configured to determine the non-linearity of the signal provided to the ADC relative to the signal provided to the auxiliary ADC.

Auxiliary ADC-based calibration for non-linearity correction of ADC

In described examples, an analog to digital converter (ADC), having an input operable to receive an analog signal and an output operable to output a digital representation of the analog signal, includes a voltage to delay (VD) block. The VD block is coupled to the input of the ADC and generates a delay signal responsive to a calibration signal. A backend ADC is coupled to the VD block, and receives the delay signal. The backend ADC having multiple stages including a first stage. A calibration engine is coupled to the multiple stages and the VD block. The calibration engine measures an error count of the first stage and stores a delay value of the first stage for which the error count is minimum.

Calibration scheme for a non-linear ADC

A non-linearity correction circuit includes a non-linearity coefficient estimation circuit. The non-linearity coefficient estimation circuit includes a data capture circuit, a non-linearity term generation circuit, a time-to-frequency conversion circuit, a bin identification circuit, a residual non-linearity conversion circuit, and a non-linearity coefficient generation circuit. The non-linearity term generation circuit is coupled to the data capture circuit. The time-to-frequency conversion circuit is coupled to the data capture circuit and the non-linearity term generation circuit. The bin identification circuit is coupled to the time-to-frequency conversion circuit. The residual non-linearity conversion circuit is coupled to the bin identification circuit. The non-linearity coefficient generation circuit is coupled to the bin identification circuit and the residual non-linearity conversion circuit.

Non-linearity correction

Pipelined analog-to-digital converters (ADCs) include a flash ADC that reduces noise tones in power supply current drawn by the flash ADC. A pipelined analog-to-digital converter (ADC) includes a flash ADC and error correction circuitry coupled to the flash ADC. The flash ADC includes a plurality of latched comparators and a plurality of driver circuits. Each of the latched comparators includes an inverting output and a non-inverting output. Each of the driver circuits is coupled to one of the latched comparators, and includes an input terminal and an output terminal. In a first subset of the driver circuits the input terminal is coupled to the inverting output of one of the latched comparators. In a second subset of the driver circuits the input terminal is coupled to the non-inverting output of one of the latched comparators.

Pipelined analog-to-digital converter

The disclosure provides a current steering digital to analog converter (DAC) that includes a plurality of DAC elements. At least one DAC element of the plurality of DAC elements is coupled to a calibration circuit. The calibration circuit includes a fixed current source coupled to a primary node of the DAC element through a first estimation switch. A digital code generator is coupled to the primary node, and generates a first digital code corresponding to a primary voltage generated at the primary node. The digital code generator generates a second digital code. A correction DAC is coupled to the digital code generator and generates a bias voltage based on the second digital code. The bias voltage is provided to the DAC element such that a current flowing through each DAC element of the plurality of DAC elements is equal.

Calibration technique for current steering DAC

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Bengaluru, India

Himanshu Varshney