Nxp Usa, Inc.

Srikanth Jagannathan

Kumar Abhishek

Nihaar N Mahatme

Christopher James Micielli

Hector Adrian Sanchez

Carl Culshaw

George Rogers Kunnen

Alexander Hoefler

Thomas Henry Luedeke

Xiankun Jin

Gayathri Bhagavatheeswaran

Manmohan Rana

Joseph Rollin Wright

Frederic Benoist

Venkannababu Ambati

Mark Shelton Cinque

Shanaka Pradeep Yapa Appuhamillage Don

A low voltage differential signaling (LVDS) receiver includes a receiver circuit including first and second inputs coupled to first and second conductive pads, respectively, and an output coupled to an input of a digital controller, and a dummy transmitter circuit including a first input coupled to receive a common mode voltage (VCM) tune signal, a second input coupled to a loopback input signal, a third input coupled to a loopback enable signal, a first output coupled to the first input of the receiver circuit, and a second output coupled to the second input of the receiver circuit. When a test mode of operation is enabled, the digital controller asserts the loopback enable signal, and the dummy transmitter circuit generates a pair of test differential signals based on the VCM tune signal, wherein the VCM tune signal varies to test the LVDS receiver over a range of common mode voltages.

Differential input receiver circuit testing with a loopback circuit

An integrated circuit includes an input/output (I/O) circuit configured to receive a first signal and a second signal and a fault detection circuit. The I/O circuit includes an I/O terminal, an I/O buffer, and a pull resistor having a first terminal coupled to the I/O terminal. The fault detection circuit is configured to determine whether a predetermined number of toggles of the first signal occurs while the second signal is held at a constant logic state, assert a fault indicator when the predetermined number of toggles occurs, and negate the fault indicator when the predetermined number of toggles does not occur.

Systems and methods for detecting faults in an analog input/output circuitry

An integrated circuit device includes general purpose input/output (I/O) circuitry having a transmit level shifter circuit in a transmit I/O circuit and a receive level shifter circuit in a receive I/O circuit. The integrated circuit device also includes an I/O pad which couples an output of the transmit level shifter circuit to an input of the receive level shifter circuit, a counter circuit, an inverter circuit coupled between the receive level shifter circuit and the counter circuit, and a logic gate. The logic gate includes a first input coupled to an output of the inverter circuit, a second input coupled to a counter_done signal from the counter circuit, and an output coupled to provide a data_out signal to an input of the transmit level shifter circuit.

Circuit configured to determine a test voltage suitable for very low voltage (VLV) testing in an integrated circuit

A circuit including a device including a first and second node. The device operating in at least an enabled mode and a disabled mode. The circuit including a voltage control circuit. The voltage control circuit including a current source for sourcing current to or sinking current from the first node during the disabled mode and a voltage difference detector including an output for providing an indication of a measured voltage difference between the first node and the second node. The voltage control circuit includes a current source control circuit including a first input to receive the indication of the measured voltage difference and an output to control current sourced to or sinked from the first node by the current source to limit a voltage difference between the first and second node based on a comparison between the indication of the measured voltage difference and an indication of a target voltage difference.

Protection circuit

A circuit includes a glitch measurement circuit and a glitch profile circuit. The glitch measurement circuit includes a first comparator to compare a glitch in a power supply voltage to a first threshold voltage, a first counter to generate a first count indicative of a time duration the first comparator indicates that the glitch trips the first threshold voltage, a second comparator to compare the glitch in the power supply voltage to a second threshold voltage different than the first threshold voltage, and a second counter to generate a second count indicative of a time duration the second comparator indicates that the glitch trips the second threshold voltage. The glitch profile circuitry utilizes the first count and the second count to generate a multi-voltage profile of the glitch, wherein the multi-voltage profile includes indications of the time durations indicated by the first count and the second count.

Glitch profiling in an integrated circuit

An integrated circuit includes a signal pad, an output buffer having an output coupled to the signal pad and having an enable input, an input buffer having an input coupled to the signal pad and having an enable input, a counter, and a gating circuit. The counter is enabled to start counting down a predetermined count value when a voltage on the signal pad is both higher than a predetermined low threshold voltage and lower than a predetermined high threshold voltage, wherein the predetermined low threshold voltage corresponds to a threshold below which a voltage corresponds to a logic level zero and the predetermined high threshold voltage corresponds to a threshold above which a voltage corresponds to a logic level one. The gating circuit is configured to, in response to the counter expiring, disable the input buffer and the output buffer.

Pad protection in an integrated circuit

A current leg located in a voltage domain where the current leg includes a transistor of a current mirror having a maximum voltage rating of less than the voltage of the voltage domain. The current leg includes a resistive element circuit to provide a first resistance during a normal mode of operation of the current leg and a different resistance during of a stress test of the transistor in a test mode of the circuit.

Stress test on circuit with low voltage transistor

A differential output driver circuit includes a drive path having a first output node that provides a first output differential signal and a second output node that provides a complementary second output differential signal to the first output differential signal, a current control transistor to control current of the drive path, and a current measurement resistor circuit located in the drive current path outside of a path segment between the first and second output node. Current flowing through the drive path flows through the current measurement resistor circuit, and a voltage across the current measurement resistor circuit is indicative of an amount of current flowing through the drive path. A transistor control circuit utilizes a voltage across the current measurement resistor circuit to control a control terminal of the current control transistor to control the current in the drive path based on the voltage across the current measurement resistor circuit.

Differential output driver circuit and method of operation

An integrated circuit includes a plurality of external terminal circuits, each having an external terminal. The integrated circuit includes a wakeup detector including a plurality of inputs. Each input of the plurality of inputs is coupled to an external terminal circuit. The wakeup detector generates an output signal indicative of an external terminal of the plurality of external terminal circuits being placed at a wakeup voltage. The integrated circuit includes a trigger generation circuit having a plurality of outputs in which each output is coupled to an external terminal circuit to generate a wake-up voltage at an external terminal of the external terminal circuit by coupling the external terminal to a power supply terminal of the integrated circuit to generate an indication of the external terminal being at the wakeup voltage at the wakeup detector when at least a portion of the integrated circuit is in a low power mode.

Low power mode testing in an integrated circuit

An embedded continuity test circuit is provided. An integrated circuit includes a bond pad and an oscillator circuit. The oscillator circuit is configured to generate an oscillator signal having a first frequency when the bond pad is coupled to a bond region of a package and a second frequency when the bond pad is not coupled to the bond region of the package.

Embedded continuity test circuit

An A/D converter includes multiple bin comparators that compare an analog voltage to corresponding bin threshold voltages to provide output signals for providing corresponding comparison results. Some of the comparators includes enable inputs that selectively enable the output signal of the bin comparator to provide the corresponding comparison result based on a corresponding comparison result from at least one other bin comparator. The A/D convertor includes an encoder that utilizes the output signals to provide encoded bit values of the digital output. The A/D converter includes a bin selection circuit that utilizes the output signals to select a voltage level based on the output signals and provides the selected voltage level to a next stage of the A/D convertor. The next stage uses the selected voltage level and the analog voltage to provide at least one lessor bit of the digital output.

Analog to digital converter

A data processing system includes an SRAM array, wherein the plurality of SRAM cells provide a physically unclonable function (PUF). A PUF evaluation engine includes a selection circuit for selecting one or more word lines coupled to the plurality of SRAM cells in response to a challenge, and a cross-coupled latch coupled to two bit lines corresponding to two different SRAM cells of the plurality of SRAM cells. The cross-coupled latch is configured to provide one of two 2-bit values depending on which of the two bit lines discharges faster upon the two different SRAM cells being selected by the selection circuit, wherein the 2-bit value is part of a digital code provided in response to the challenge.

SRAM based physically unclonable function and method for generating a PUF response

A circuit includes a transmitter circuit which includes a single-to-complementary circuit, a driver stage, and a pre-emphasis control circuit. The single-to-complementary circuit generates complementary output signals from a single ended input signal. The driver stage includes inputs to receive the complementary output signals, the driver stage includes a main driver circuit and a pre-emphasis driver circuit, and the pre-emphasis driver circuit is active during transitions of the complementary output signals to provide additional current for the driver stage. The pre-emphasis control circuit includes an RC pulse generation circuit in which the RC pulse generation circuit includes a capacitance and a resistance, and the RC pulse generation circuit provides, based on edges of a signal, pulses having a duration based on an RC time constant of the capacitance and resistance. The pre-emphasis driver circuit is active to provide additional current for the driver stage in response to the pulses.

Transmitter circuit having a pre-emphasis driver circuit

A circuit includes a first external terminal, a first lower resolution analog-to-digital converter (LRADC) coupled to the external terminal and configured to perform a first conversion of an analog signal received at the external terminal to a digital value, and a higher resolution analog-to-digital converter (HRADC). The HRADC is configured to selectively receive the analog signal from the first external terminal based on the digital value. When the digital value outputted by the first LRADC indicates a change in value of the received analog signal, the HRADC is provided with the analog signal and performs a second conversion of the analog signal to a second digital value. The first LRADC has a lower conversion resolution as compared to the HRADC.

Circuit with analog-to-digital converters of different conversion resolutions

A comparator circuit includes a first transistor have a control electrode coupled to a first input voltage, a first current electrode coupled to a second input voltage, and a second current electrode coupled to a first circuit node. The circuit also includes a first inverter coupled to a first voltage supply terminal and having a first input coupled to the first circuit node and an output, a second transistor having a control electrode coupled to the output of the first inverter, and an active resistive element coupled in series between the first circuit node and a first current electrode of the second transistor.

Growing community of inventors

Austin, TX, United States of America

Srikanth Jagannathan