In one aspect, an analog-to-digital converter circuit includes a transimpedance amplifier including a feedback capacitor electrically connected between an inverting or a non-inverting input of the transimpedance amplifier and an output of the transimpedance amplifier. The circuit includes an hourglass switch electrically connected on a first side to a first input and a second input, and electrically connected on a second side to the non-inverting input and the inverting input. A fine input current to the transimpedance amplifier is received at the first and second inputs. In a first mode, the hourglass switch electrically connects the first input to the non-inverting input and the second input to the inverting input, and in a second mode, the hourglass switch electrically connects the second input to the non-inverting input and the first input to the inverting input.

A delta-sigma modulator generates a bitstream signal from a differential input signal including a first input signal and a second input signal by repeating a first operation and a second operation alternately. The delta-sigma modulator includes a first sampling capacitor, a second sampling capacitor, a third sampling capacitor, a fourth sampling capacitor, an operational amplifier, a first feedback capacitor, a second feedback capacitor, and a quantizer.

A delta-sigma modulator generates a bitstream signal from a differential input signal including a first input signal and a second input signal by repeating a first operation and a second operation alternately. The delta-sigma modulator includes a first sampling capacitor, a second sampling capacitor, a third sampling capacitor, a fourth sampling capacitor, an operational amplifier, a first feedback capacitor, a second feedback capacitor, and a quantizer.

In one aspect, an analog-to-digital converter circuit includes a transimpedance amplifier including a feedback capacitor electrically connected between an inverting or a non-inverting input of the transimpedance amplifier and an output of the transimpedance amplifier. The circuit includes an hourglass switch electrically connected on a first side to a first input and a second input, and electrically connected on a second side to the non-inverting input and the inverting input. A fine input current to the transimpedance amplifier is received at the first and second inputs. In a first mode, the hourglass switch electrically connects the first input to the non-inverting input and the second input to the inverting input, and in a second mode, the hourglass switch electrically connects the second input to the non-inverting input and the first input to the inverting input.

Systems, methods, and devices provide sampling for data converters. Methods include receiving a voltage from a voltage source, and identifying transconductance parameters and resistance parameters associated with a data converter, the transconductance parameters identifying a transconductance of the data converter. Methods also include selecting a resistor from a plurality of dynamically selectable resistors based on the resistance parameters, generating, using a programmable gain amplifier, a current based, at least in part, on the selected resistor and the received voltage, and providing the current to the data converter.

The techniques described herein relate to overcurrent detection with multi-bit analog-to-digital converters (ADCs). An example apparatus includes a multi-bit analog-to-digital converter (ADC) configured to convert an analog signal into a multi-bit digital signal. The example apparatus further includes a threshold detector configured to generate an output signal indicative of an overcurrent condition after a detection of at least a first number of bits of the multi-bit digital signal satisfying a threshold.