Nxp Usa, Inc.

Kumar Abhishek

Yi Zheng

Srikanth Jagannathan

Xiankun Jin

Neha Srivastava

Joseph Rollin Wright

Frederic Benoist

Mark Lehmann

Aditya Musunuri

Sandeep Singh Jasrotia

Nishant Kumar

Subhashrahul Shekhar

Vivek Kumar Yadav

Kushagra Khorwal

In an integrated circuit, a first always on (AON) domain generates an isolation signal to enter standby mode. A switchable power domain propagates the isolation signal. A voltage level detector outputs an indicator which indicates whether a voltage of the switchable power supply is above or below a voltage threshold. An isolation wrapper circuit includes a pass-through latch selectively enabled based on the output of the voltage level detector. The pass-through latch receives the propagated isolation signal and provides a value of the propagated isolation signal at its output while enabled, but maintains a latched value at its output, regardless of changes in value of the propagated isolation signal, while disabled. The wrapper circuit also includes an isolation circuit which receives signals from circuitry within the switchable power domain and selectively isolates the received signals from a second AON power domain based on the output of the pass-through latch.

System on a chip (SoC) having a low power mode of operation

Systems and methods for managing asynchronous resets in an SoC have been described. In an illustrative, non-limiting embodiment, a reset generation circuit in an SoC, may include a first reset generation circuit configured to enable a first reset signal based, at least in part, upon a clock signal and an indication to reset. The reset generation circuit may also include a second reset generation circuit coupled to the first reset generation circuit, in which the second reset generation circuit is configured to enable a second reset signal after the first reset signal is enabled. The first reset signal and the second reset signal are both provided to a component of the SoC.

Architecture for managing asynchronous resets in a system-on-a-chip

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

A system-on-chip (SoC) having a switchable power domain capable of being placed in a standby mode during which a power supply of the switchable power domain is gated and having an always-on power domain. The always-on power domain includes an input sampling circuit, and the switchable power domain includes an input/output (IO) circuit configured to, during normal operation, receive data at a corresponding signal pin when an input buffer of the IO circuit is enabled, in which the corresponding signal pin is coupled to the input sampling circuit. The input sampling circuit is configured to, while the switchable power domain is entering the standby mode but before the power supply is gated, provide an override input enable signal to enable the input buffer of the IO circuit, sample an input bit value on the corresponding signal pin, and store the sampled bit value to provide an injection current fault indicator.

Fault detection during entry to or exit from low power mode

A packaged die including a first and a second power supply pad configured to provide a first and a second power supply voltage, respectively, and circuitry powered by the first power supply voltage. A power pad handling circuitry includes a selectively enablable pull-down path coupled between the first power supply pad and the second power supply pad, a storage circuit configured to store a pull-down path enable bit, a clock input coupled to receive a boot clock, and an asynchronous input coupled to receive a power-on-reset (POR) signal. In response to assertion of the POR signal, the pull-down pat is enabled regardless of any signal received at the clock input and regardless the value of the pull-down path enable bit. When reset has completed, a value of the pull-down path enable bit is provided upon an active edge of the boot clock to selectively enable the pull-down path.

Power supply handling for multiple package configurations

Analog-to-digital converters (ADCs) of an integrated circuit includes a first set of ADCs and second set of ADCs in which the ADCs of the first set are of a different type than the ADCs of the second set. On-chip testing of the ADCs includes calibrating an N-bit differential digital-to-analog converter (DAC) and storing a pair of calibration codes for each of 2possible DAC input codes for the DAC in an on-chip memory. The first set of ADCs is tested using the pairs of calibration codes stored in the on-chip memory and a full N-bit resolution of the DAC. Subsequently, the second set of ADCs is tested using pairs of calibration codes corresponding to a reduced M-bit resolution of the DAC, in which M is less than N. During the testing of the second set of ADCs, a portion of the calibration codes stored in the on-chip memory is overwritten.

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Bee Cave, TX, United States of America

Kumar Abhishek