Several circuits and methods for transferring an input data signal in a digital isolator are disclosed. In an embodiment, the digital isolator includes an isolation element, input circuit, and output circuit. The isolation element includes at least one input node and at least one output node, the input circuit is electronically coupled to the input node and generates modulated differential data signals based on modulating the input data signal on a carrier signal. The input circuit operates using a first supply voltage with respect to a first ground. The output circuit is electronically coupled to the output node to receive the modulated differential data signals, operates using a second supply voltage with respect to a second ground and includes a frequency-shift keying demodulator configured to generate a demodulated data signal in response to detection of presence of the carrier signal. The output circuit further generates an output data signal.

A rectifier stage includes a differential input transistor pair coupled between a reference voltage node and an intermediate node, and a load circuit coupled between the intermediate node and a supply voltage node. The differential input transistor pair receives a radio-frequency amplitude modulated signal. A rectified signal indicative of an envelope of the radio-frequency amplitude modulated signal is produced at the intermediate node. An amplifier stage coupled to the intermediate node produces an amplified rectified signal at an output node that is indicative of the envelope of the radio-frequency amplitude modulated signal. The rectifier stage includes a resistive element coupled between the intermediate node and the supply voltage node in parallel to the load circuit.

Methods and apparatus embodiments to communicate data via a digital isolator by receiving an input data stream having first and second states, generating a first pulse train for the first state and a second pulse train for the second state. The first and second pulse types are transmitted across a voltage barrier of a digital signal isolator and received by a receive channel. The first and second pulse trains are processed to recover the input data stream in an output data stream. Data/System integrity functionality can identify fault conditions from an alteration of transmitted pulses.

Methods and apparatus for a signal isolator having inductive and capacitive coupling. In embodiments, magnetic and electric fields are coupled by coils and capacitive plates. In embodiments, a floating plate can enable a top and bottom capacitive plate to be offset from each other.

Advanced detectors for vector signaling codes are disclosed which utilize multi-input comparators, generalized on-level slicing, reference generation based on maximum swing, and reference generation based on recent values. Vector signaling codes communicate information as groups of symbols which, when transmitted over multiple communications channels, may be received as mixed sets of symbols from different transmission groups due to propagation time variations between channels. Systems and methods are disclosed which compensate receivers and transmitters for these effects and/or utilize codes having increased immunity to such variations, and circuits are described that efficiently implement their component functions.

Several circuits and methods for transferring an input data signal in a digital isolator are disclosed. In an embodiment, the digital isolator includes an isolation element, input circuit, and output circuit. The isolation element includes at least one input node and at least one output node, the input circuit is electronically coupled to the input node and generates modulated differential data signals based on modulating the input data signal on a carrier signal. The input circuit operates using a first supply voltage with respect to a first ground. The output circuit is electronically coupled to the output node to receive the modulated differential data signals, operates using a second supply voltage with respect to a second ground and includes a frequency-shift keying demodulator configured to generate a demodulated data signal in response to detection of presence of the carrier signal. The output circuit further generates an output data signal.

A regenerative differential receiver includes, for example, a transformer arranged to receive a modulated differential signal. A first detector is arranged to source a first output current for indicating a first power level in response to falling voltage of a first line of the modulated differential signal. A second detector is arranged to sink a second output current for indicating a second power level in response to rising voltage of a first line of the modulated differential signal. A cross-coupled latch is arranged to latch a state in response to the first and second power levels. The cross-coupled latch provides, for example, weak non-linear regeneration for increasing receiver gain and maximum operating frequencies.

Methods and apparatus embodiments to communicate data via a digital isolator by receiving an input data stream having first and second states, generating a first pulse train for the first state and a second pulse train for the second state. The first and second pulse types are transmitted across a voltage barrier of a digital signal isolator and received by a receive channel. The first and second pulse trains are processed to recover the input data stream in an output data stream. Data/System integrity functionality can identify fault conditions from an alteration of transmitted pulses.

Methods and systems are described for communication of data over a communications bus at high speed and high pin efficiency, with good resilience to common mode and other noise. Pin efficiencies of 100% may be achieved even for bus widths of four or fewer wires. Information to be transmitted is encoded as words of a vector signaling code, each word comprising multiple values transmitted as a group over the communications bus. Subsets of the vector signaling code have distinct group characteristics, which are discernable on transmission and are used to facilitate decoding on reception.

Advanced detectors for vector signaling codes are disclosed which utilize multi-input comparators, generalized on-level slicing, reference generation based on maximum swing, and reference generation based on recent values. Vector signaling codes communicate information as groups of symbols which, when transmitted over multiple communications channels, may be received as mixed sets of symbols from different transmission groups due to propagation time variations between channels. Systems and methods are disclosed which compensate receivers and transmitters for these effects and/or utilize codes having increased immunity to such variations, and circuits are described that efficiently implement their component functions.