Abstract: An apparatus is disclosed for pipelined analog-to-digital conversion. In an example aspect, the apparatus includes a pipelined analog-to-digital converter (ADC). The pipelined ADC includes a first stage and a second stage. The first stage includes a sampler and a quantizer coupled to the sampler. The first stage also includes a current distribution circuit coupled to the sampler. The second stage includes a sampler coupled to the current distribution circuit and a quantizer coupled to the sampler of the second stage.

Abstract: A compute-in-memory bitcell is provided that includes a pair of cross-coupled inverter for storing a stored bit. The compute-in-memory bitcell includes a logic gate for multiplying the stored bit with an input vector bit. An output node for the logic gate connects to a second plate of a capacitor. A first plate of the capacitor connects to a read bit line.

Abstract: A compute-in-memory bitcell is provided that includes a pair of cross-coupled inverters for storing a stored bit. The compute-in-memory bitcell includes a logic gate for multiplying the stored bit with an input vector bit. An output node for the logic gate connects to a second plate of a capacitor. A first plate of the capacitor connects to a read bit line. A write driver controls a power supply voltage to the cross-coupled inverters, the first switch, and the second switch to capacitively write the stored bit to the pair of cross-coupled inverters.

Abstract: An apparatus is disclosed for pipelined analog-to-digital conversion. In an example aspect, the apparatus includes a pipelined analog-to-digital converter (ADC). The pipelined ADC includes a first stage and a second stage. The first stage includes a sampler and a quantizer coupled to the sampler. The first stage also includes a current distribution circuit coupled to the sampler. The second stage includes a sampler coupled to the current distribution circuit and a quantizer coupled to the sampler of the second stage.

Abstract: Certain aspects of the present disclosure provide techniques for efficient depthwise convolution. A convolution is performed with a compute-in-memory (CIM) array to generate CIM output, and at least a portion of the CIM output corresponding to a first output data channel, of a plurality of output data channels in the CIM output, is written to a digital multiply-accumulate (DMAC) activation buffer. A patch of the CIM output is read from the DMAC activation buffer, and weight data is read from a DMAC weight buffer. Multiply-accumulate (MAC) operations are performed with the patch of CIM output and the weight data to generate a DMAC output.

Abstract: An apparatus is disclosed for analog-to-digital conversion. In an example aspect, the apparatus includes an analog-to-digital converter (ADC). The ADC includes a reference-crossing detector having an input and an output. The ADC also includes a ramp generator coupled between the output of the reference-crossing detector and the input of the reference-crossing detector. The ADC further includes a voltage shifter coupled between the output of the reference-crossing detector and the input of the reference-crossing detector.

Abstract: An apparatus is disclosed for analog-to-digital conversion. In an example aspect, the apparatus includes an analog-to-digital converter (ADC). The ADC includes a reference-crossing detector having an input and an output. The ADC also includes a ramp generator coupled between the output of the reference-crossing detector and the input of the reference-crossing detector. The ADC further includes a voltage shifter coupled between the output of the reference-crossing detector and the input of the reference-crossing detector.

Abstract: A compute-in-memory bitcell is provided that includes a pair of cross-coupled inverters for storing a stored bit. The compute-in-memory bitcell includes a logic gate formed by a pair of switches for multiplying the stored bit with an input vector bit. A controller controls the pair of switches responsive to a sign bit during a computation phase of operation and controls the pair of switches responsive to a magnitude bit during an execution phase of operation.

Abstract: A compute-in-memory bitcell is provided that includes a pair of cross-coupled inverters for storing a stored bit. The compute-in-memory bitcell includes a logic gate formed by a pair of switches for multiplying the stored bit with an input vector bit. A controller controls the pair of switches responsive to a sign bit during a computation phase of operation and controls the pair of switches responsive to a magnitude bit during an execution phase of operation.

Abstract: Various embodiments include devices and methods for a multi-bit multiplier-accumulator (MAC). Some embodiments may include an analog adder having a first adder capacitor. The first adder capacitor may add a plurality of single-bit MAC outputs by receiving the plurality of single-bit MAC outputs from a plurality of single-bit MACs, and storing the plurality of single-bit MAC outputs. In some embodiments, the analog adder may output a multi-bit MAC output based on addition of the stored plurality of single-bit MAC outputs.

Abstract: A compute-in-memory bitcell is provided that includes a pair of cross-coupled inverters for storing a stored bit. The compute-in-memory bitcell includes a logic gate formed by a pair of switches for multiplying the stored bit with an input vector bit. A controller controls the pair of switches responsive to a sign bit during a computation phase of operation and controls the pair of switches responsive to a magnitude bit during an execution phase of operation.

Abstract: A compute-in-memory bitcell is provided that includes a pair of cross-coupled inverters for storing a stored bit. The compute-in-memory bitcell includes a logic gate for multiplying the stored bit with an input vector bit. An output node for the logic gate connects to a second plate of a capacitor. A first plate of the capacitor connects to a read bit line. A write driver controls a power supply voltage to the cross-coupled inverters, the first switch, and the second switch to capacitively write the stored bit to the pair of cross-coupled inverters.

Abstract: Certain aspects provide a circuit for analog-to-digital conversion. The circuit generally includes a flash analog-to-digital converter (ADC) having a plurality of comparators, each comparator being configured to compare an input voltage to a reference voltage; and a calibration circuit coupled to the flash ADC and configured to tune the reference voltage prior to a conversion operation by the flash ADC.

Abstract: A compute-in-memory bitcell is provided that includes a pair of cross-coupled inverter for storing a stored bit. The compute-in-memory bitcell includes a logic gate for multiplying the stored bit with an input vector bit. An output node for the logic gate connects to a second plate of a capacitor. A first plate of the capacitor connects to a read bit line.

Abstract: A time-multiplexed group of MAC circuits for a machine learning application is provided in which at least one MAC circuit in the time-multiplexed group also functions as a capacitive-digital-to-analog converter (CDAC) within a successive approximation analog-to-digital converter (ADC). A comparator in the ADC is shared by the time-multiplexed group of MAC circuits.

Abstract: A bootstrapped switch circuit includes an auxiliary loop circuit for assisting the boosting of a bootstrap voltage in a main loop circuit having a bootstrapped switch transistor. The boosted bootstrap voltage switches on the bootstrapped switch transistor so that an input voltage signal may conduct through the bootstrapped switch transistor to charge a sampling node.

Abstract: A bootstrapped switch circuit includes an auxiliary loop circuit for assisting the boosting of a bootstrap voltage in a main loop circuit having a bootstrapped switch transistor. The boosted bootstrap voltage switches on the bootstrapped switch transistor so that an input voltage signal may conduct through the bootstrapped switch transistor to charge a sampling node.

Abstract: Methods and apparatus for digitally controlling a common-mode voltage of a comparator. An example comparator circuit generally includes a first comparator and a sensing circuit configured to digitally track a common-mode voltage of the first comparator. The comparator circuit may further include a first capacitive array having a common terminal coupled to a first input of the first comparator and selectively coupled to an input of the sensing circuit. The comparator circuit may further include a second capacitive array having a common terminal coupled to a second input of the first comparator and selectively coupled to the input of the sensing circuit.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for performing background noise estimation using a circular histogram noise figure (CHNF) in an analog-to-digital converter (ADC) circuit with redundancy. The estimated noise may be used to reduce the noise (e.g., comparator noise) in the ADC circuit. One example ADC circuit generally includes at least one of a comparator or a digital-to-analog converter (DAC) and at least one digital feedback input. The at least one digital feedback input is coupled to the at least one of the comparator or the DAC and is configured to adjust at least one parameter of the at least one of the comparator or the DAC based on at least a portion of an output of the ADC circuit.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for calibrating time-interleaved analog-to-digital converter (ADC) circuits and generating a suitable signal for such calibration. Certain aspects provide a signal generator for calibrating a time-interleaved ADC circuit having a plurality of channels. The signal generator generally includes a pattern generator configured to receive a periodic signal and to output a bitstream based on the periodic signal and a conversion circuit having an input coupled to an output of the pattern generator and configured to generate a waveform based on the bitstream. The bitstream has a bit pattern with a total number of bits that shares no common factor with a number of the channels and includes a relatively lower frequency component combined with a relatively higher frequency component.