Taiwan Semiconductor Manufacturing Comp. Ltd.

Silicon Laboratories Inc.

Skyworks Solutions, Inc.

Mohammad Al-Shyoukh

Alexander Kalnitsky

Stefan N Mastovich

Percy Neyra

Krishna Pentakota

Alex Kalnitsky

Chen-Yi Lee

Shih-Fen Huang

Yu-Chang Jong

Pei-Lun Wang

Dah-Chuen Ho

In at least one embodiment, a method for operating a receiver includes configuring a receiver front-end circuit of the receiver according to a selected power consumption configuration. The method includes adjusting a quiescent current of a programmable flat gain stage coupled to the receiver front-end circuit according to the selected power consumption configuration to compensate for any gain loss of the receiver front-end circuit in the selected power consumption configuration. The selected power consumption configuration may be a reduced power consumption configuration and the programmable flat gain stage may be configured to at least partially compensate for the gain loss of the receiver front-end circuit in the reduced power consumption configuration.

Receiver front end for digital isolators

A current reference which includes a tracking voltage generator including a flipped gate transistor, a first transistor connected with the flipped gate transistor in a Vgs subtractive arrangement, an output node providing a tracking voltage which has a positive or negative temperature dependency based on the flipped gate transistor and the first transistor, and a second transistor connected to the output node; an amplifier to receive the tracking voltage and output an amplified signal; a control transistor to receive the amplified signal; a control resistor connected in series with the control transistor; and a current mirror to receive and mirror a reference current to at least one external device, the current mirror including mirroring pairs having a corresponding mirroring resistor coupled in series with a corresponding mirroring transistor, the mirroring resistor of at least one of the mirroring pairs having a serpentine structure.

Flipped gate current reference

A voltage reference includes a flipped gate transistor configured to receive a first current. The voltage reference further includes a first transistor configured to receive a second current, the first transistor having a first leakage current, wherein the first transistor is connected with the flipped gate transistor in a Vgs subtractive arrangement. The voltage reference further includes an output node configured to output a reference voltage, the output node connected to the first transistor. The voltage reference further includes a second transistor connected to the output node, the second transistor having a second leakage current, wherein the first leakage current is substantially equal to the second leakage current.

Flipped gate voltage reference and method of using

A receiver front-end includes a first peaking gain stage configured to amplify a received differential pair of signals received on an input differential pair of nodes. The first peaking gain stage has a first frequency response including a first peak gain at or near a carrier frequency in a first pass band. The first peak gain occurs just prior to a first cutoff frequency. A second peaking gain stage is configured to amplify a differential pair of signals generated by the first peaking gain stage. The second peaking gain stage has a high input impedance and a second frequency response including a second peak gain at or near the carrier frequency in a second pass band. The second peak gain occurs just prior to a second cutoff frequency. The first peaking gain stage and the second peaking gain stage have a cascaded peak gain at or near the carrier frequency.

A voltage reference includes a flipped gate transistor coupled between a first node configured to carry an operating voltage and a second node configured to carry a negative supply voltage. A first transistor and a second transistor are coupled in series between the first node and the second node, a gate of the first transistor is coupled with a gate of the flipped gate transistor, and a gate of the second transistor is configured to receive the negative supply voltage. An output node between the first transistor and the second transistor is configured to output a reference voltage, and a current source coupled between the output node and the second node is configured to supply a current through the first transistor based on a current through the flipped gate transistor.

A tracking voltage generator, the latter including: a first transistor having a first leakage current and which is coupled with the flipped gate transistor so that a difference between a gate-source voltage (Vgs) of a flipped gate transistor and the first transistor is approximately equal to a bandgap voltage of a semiconductor material from which the tracking voltage generator is formed; an output node providing a tracking voltage which has a positive or negative temperature dependency based on the flipped gate transistor and the first transistor; and a second transistor connected to the output node and which has a second leakage current. A current reference includes: the tracking voltage generator; an amplifier to receive the tracking voltage and output an amplified signal; a control transistor to receive the amplified signal and conduct a reference current therethrough; and a control resistor connected in series with the control transistor.

Flipped gate current reference and method of using

A method for calibrating an isolator product includes generating a differential pair of signals on a differential pair of nodes at an input of a demodulator circuit of a receiver signal path of a first integrated circuit die of the isolator product based on a received differential pair of signals. The method includes generating a diagnostic output signal having a level corresponding to an average amplitude of the differential pair of signals. The method includes driving the diagnostic output signal to an output terminal of the isolator product. The method may include transmitting a diagnostic signal using a carrier signal having a frequency by a second integrated circuit die via an isolation channel. The method may include, during the transmitting, sweeping the frequency of the carrier signal across a frequency band. The method may include, during the sweeping, capturing the diagnostic output signal via the output terminal.

Calibration of digital isolators

A receiver signal path includes a high pass filter that centers a received differential pair of signals around a common mode voltage to generate a centered received differential pair of signals. The receiver signal path includes a demodulator that removes a carrier signal from the centered received differential pair of signals to generate a demodulated signal and generates a logic signal based on the demodulated signal and a predetermined threshold signal. The demodulator includes a differential stage including an extremum selector circuit that generates the demodulated signal based on the centered received differential pair of signals. The demodulated signal corresponds to a mean level of the rectified version of the centered received differential pair of signals. The differential stage includes a second circuit that provides the reference signal based on the predetermined threshold signal. The logic signal is based on a comparison of the demodulated signal to the reference signal.

Demodulator/detector for digital isolators

A receiver signal path includes a programmable flat gain stage configured to provide an amplified differential pair of signals based on a first frequency response having a selectable flat gain and a differential input pair of signals received on an input differential pair of nodes. The receiver signal path includes a peaking gain stage configured to generate a second amplified differential pair of signals based on the amplified differential pair of signals according to a second frequency response including a first peak gain at or near a carrier frequency in a first pass band. The first peak gain occurs just prior to a first cutoff frequency of the peaking gain stage. The programmable flat gain stage and the peaking gain stage are configured as a variable peaking gain stage. The selectable flat gain is selectively programmed based on a predetermined power consumption of a receiver path.

Receiver intermediate variable gain stage for isolator products

A power transfer device includes a first power supply node, a second power supply node, and an oscillator circuit configured to convert an input DC signal across the first power supply node and the second power supply node into an AC signal on a differential pair of nodes comprising a first node and a second node in response to a control signal. The oscillator circuit includes a regulated power supply node and an active shunt regulator circuit configured to clamp a peak voltage level across the regulated power supply node and the second power supply node to a clamped voltage level. The clamped voltage level is linearly related to a first voltage level on the first power supply node.

Power resonator with wide input voltage range for isolated power transfer

A power transfer device includes an oscillator circuit having a first node, a second node, and a control terminal. The oscillator circuit includes a cascode circuit comprising transistors having a first conductivity type and a first breakdown voltage. The cascode circuit is coupled to the control terminal, the first node, and the second node. The oscillator circuit includes a latch circuit coupled between the cascode circuit and a first power supply node. The latch circuit includes cross-coupled transistors having the first conductivity type and a second breakdown voltage. The first breakdown voltage is greater than the second breakdown voltage. The oscillator circuit may be configured to develop a pseudo-differential signal on the first node and the second node. The pseudo-differential signal may have a peak voltage of at least three times a voltage level of an input DC signal on a second power supply node.

Power transfer device using an oscillator

A level shifter includes a flying capacitor having a first plate and a second plate. The level shifter includes a circuit coupled to the first plate and coupled to the second plate. The circuit is configured to receive a received signal having a logic state using a first voltage domain and configured to generate a symmetrical output signal having the logic state using a second voltage domain based on charge stored by the flying capacitor. The level shifter has a propagation delay from the received signal to the symmetrical output signal of less than one nanosecond with negligible duty cycle distortion.

Capacitive level shifter

A current reference comprising: a control resistor; a tracking voltage generator including: a first, flipped gate transistor having a first size; and a second transistor having a second size; wherein the tracking voltage generator is configured to output a tracking voltage having a first temperature dependency based on a ratio of the second size to the first size, the temperature dependency thereby being substantially equal to a second temperature dependency of the control resistor; and an amplifier circuit configured to receive the tracking voltage and maintain a voltage at a first terminal of the control resistor, the voltage being substantially equal to the tracking voltage; wherein the current reference thereby is configured to maintain a reference current through the control resistor at a constant value.

A technique for attenuating common mode transient events uses a differential receiver circuit including a band-stop filter having a stopband faround a notch frequency fof a received signal. The differential receiver circuit includes a first high-pass filter coupled in series with the band-stop filter. The notch frequency fis less than a carrier frequency fof a signal received by the differential receiver circuit. The band-stop filter may include a buffer circuit and a notch filter coupled in series with the buffer circuit. The notch filter may have a second stopband around the notch frequency f. The differential receiver circuit may have a propagation delay that is independent of a pulse width of common mode transient energy attenuated by the differential receiver circuit.

Growing community of inventors

Cedar Park, TX, United States of America

Mohammad Al-Shyoukh