Technologies are provided for time-to-digital conversion without reliance on a clocking signal. Some embodiments of the technologies include a clockless TDC apparatus that can map continuous pulse-widths to binary bits represented via an iterative chaotic map (e.g., tent map, Bernoulli shift map, or similar). The clockless TDC apparatus can convert separated pulses to a single asynchronous digital pulse that turns on when a sensor detects a first pulse and turns off when the sensor detects a second pulse. The asynchronous digital pulse can be iteratively stretched and folded in time according to the chaotic map. The clockless TDC can generate a binary sequence that represents symbolic dynamics of the chaotic map. The process can be implemented by using an iterative time delay component until a precision of the binary output is either satisfied or overwhelmed by noise or other structural fluctuations of the TDC apparatus.

A signal folding device receives an input signal, and performs frequency modulation on a plurality of first analog signals based on the input signal to obtain a plurality of modulated first analog signals, where a frequency difference between two adjacent first analog signals in the plurality of modulated first analog signals is the same. The signal folding device may filter the plurality of modulated first analog signals based on a specified bandwidth to obtain a second analog signal, and demodulate the second analog signal to obtain an output signal. The output signal is a folded signal of the input signal within a target amplitude, and the second analog signal is an analog signal within the bandwidth.

An image sensor includes; a pixel array disposed in a Bayer pattern and including pixels which respectively generate electrical charge according to received light incident, and an analog logic configured to convert an analog signal output from at least one pixel among the pixels into a first digital code using analog-to-digital conversion, and convert the first digital code into a second digital code by adjusting low-order bits of the first digital code in response to a control signal.

The amplifier load current cancellation in a current integrator comprises applying an input current to an operational transconductance amplifier provided with an integration capacitor for current integration, leading an output current of the operational transconductance amplifier through a sensing resistor, thus producing a voltage drop over the sensing resistor, generating a cancellation current dependent on the voltage drop over the sensing resistor, and injecting the cancellation current to the output current, before or after the output current passes the sensing resistor, thus eliminating a dependence of the output current on the input current.

Technologies are provided for time-to-digital conversion without reliance on a clocking signal. The technologies include a clockless TDC apparatus that can map continuous pulse-widths to binary bits represented via an iterative chaotic map (e.g., tent map, Bernoulli shift map, or similar). The clockless TDC apparatus can convert separated pulses to a single asynchronous digital pulse that turns on when a sensor detects a first pulse and turns off when the sensor detects a second pulse. The asynchronous digital pulse can be iteratively stretched and folded in time according to the chaotic map. The clockless TDC can generate a binary sequence that represents symbolic dynamics of the chaotic map. The process can be implemented by using an iterative time delay component until a precision of the binary output is either satisfied or overwhelmed by noise or other structural fluctuations of the TDC apparatus.

An analog-to-digital converter (ADC) having an input operable to receive an input voltage, V.sub.IN, and an output operable to output a digital code representative of V.sub.IN, the ADC including: a voltage-to-delay circuit having an input and an output, the input of the voltage-to-delay circuit coupled to the input of the ADC; a folding circuit having an input and an output, the input of the folding circuit coupled to the output of the voltage-to-delay circuit; and a time delay-based analog-to-digital converter backend having an input and a digital code output coupled to the output of the ADC, the input of the time delay-based analog-to-digital converter backend coupled to the output of the folding circuit.

A method for light-to-digital conversion includes setting a time integrator circuit into a reference condition and starting to integrate charge from a sensor device for the duration of an integration time. An integration signal is generated and is indicative of the integrated charge. The integration signal is compared with an adjustable reference signal. A first count is generated when the comparison indicates that the integration signal has reached an integration range, wherein the integration range is defined by a low and a high voltage. A second count is generated when the comparison indicates that the integration signal has reached the adjustable reference signal. The adjustable reference signal is incremented in discrete steps when a second count has been generated. Then, the time integrator circuit is reset into the reference condition, when the comparison indicates that the integration signal has reached the integration range. The generated first counts is collected as first count signal and the generated second counts are collected as second count signal. Finally, a digital output signal is generated depending on the first count signal and the second count signal.

Technologies are provided for time-to-digital conversion without reliance on a clocking signal. The technologies include a clockless TDC apparatus that can map continuous pulse-widths to binary bits represented via an iterative chaotic map (e.g., tent map, Bernoulli shift map, or similar). The clockless TDC apparatus can convert separated pulses to a single asynchronous digital pulse that turns on when a sensor detects a first pulse and turns off when the sensor detects a second pulse. The asynchronous digital pulse can be iteratively stretched and folded in time according to the chaotic map. The clockless TDC can generate a binary sequence that represents symbolic dynamics of the chaotic map. The process can be implemented by using an iterative time delay component until a precision of the binary output is either satisfied or overwhelmed by noise or other structural fluctuations of the TDC apparatus.

A memory device and an operation method thereof are provided. The memory device includes: a memory array including a plurality of memory cells for storing a plurality of weights; a multiplication circuit for performing bitwise multiplication on a plurality of input data and the weights to generate a plurality of multiplication results, wherein in performing bitwise multiplication, the memory cells generate a plurality of memory cell currents; a digital accumulating circuit for performing a digital accumulating on the multiplication results; an analog accumulating circuit for performing an analog accumulating on the memory cell currents to generate a first MAC operation result; and a decision unit for deciding whether to perform the analog accumulating; the digital accumulating or a hybrid accumulating, wherein in performing the hybrid accumulating, whether the digital accumulating circuit is triggered is based on the first MAC operation result.

The amplifier load current cancellation in a current integrator comprises applying an input current to an operational transconductance amplifier provided with an integration capacitor for current integration, leading an output current of the operational transconductance amplifier through a sensing resistor, thus producing a voltage drop over the sensing resistor, generating a cancellation current dependent on the voltage drop over the sensing resistor, and injecting the cancellation current to the output current, before or after the output current passes the sensing resistor, thus eliminating a dependence of the output current on the input current.