Abstract: A high voltage input receiver with hysteresis using low voltage transistors is disclosed. In one embodiment, an input receiver circuit includes a hysteresis comparator circuit, based on a plurality of low voltage transistors, for generating a first output voltage by comparing an external voltage and a reference voltage and a stress protection circuit for preventing the plurality of low voltage transistors of the hysteresis comparator circuit from exceeding their reliability limits. In addition, the reference voltage is used to set a positive trip point and a negative trip point. Moreover, the input receiver circuit includes a source follower circuit for transferring the first output voltage to an output node of the source follower circuit from a voltage level of a VDDIO to a voltage level of a VDD.

Abstract: A method includes controllably generating a first bias voltage from a supply voltage to be within an upper tolerable limit of an operating voltage of an IO receiver, and controllably generating a second bias voltage from an external voltage supplied through an IO pad to be within the upper tolerable limit of the operating voltage of the IO receiver. The method also includes deriving an output voltage from the first bias voltage during a normal condition and a tolerant condition, and deriving the output voltage from the second bias voltage during a failsafe condition. The tolerant condition is a mode of operation where the external voltage supplied through the IO pad varies from zero to a value higher than the supply voltage, and the failsafe condition is a mode of operation where the supply voltage is zero.

Abstract: Disclosed are a method, system and apparatus for an improved fail safe I/O driver with pad feedback slew rate control are disclosed. In one embodiment, a pad driver circuit includes a pad node, an NMOS component, a feedback capacitor between the pad node and a gate of the NMOS component to control slew rate across a range of capacitor loads, a switch circuit between the pad node and the feedback capacitor, and a signal generator to generate a signal to control the switch circuit. The switch circuit to maintain a main driver circuit and a pre-driver circuit of the pad driver circuit in a fail safe state when an integrated circuit that includes the pad driver circuit is in the fail safe state. The pad driver circuit may include a PMOS component.

Abstract: A method includes controllably generating a first bias voltage from a supply voltage to be within an upper tolerable limit of an operating voltage of one or more constituent active circuit element(s) of an Input/Output (IO) core device of an integrated circuit (IC) to be interfaced with an IO pad, and controllably generating a second bias voltage from an external voltage supplied through the IO pad to be within the upper tolerable limit of the operating voltage of the one or more constituent active circuit element(s) of the IO core device to be interfaced with the IO pad. The method also includes controllably utilizing a control signal generated by the IO core to derive an output bias voltage from the first bias voltage during a driver mode of operation or the second bias voltage during a failsafe mode of operation and a tolerant mode of operation.

Abstract: A method includes controllably generating a first bias voltage from a supply voltage to be within an upper tolerable limit of an operating voltage of an IO receiver, and controllably generating a second bias voltage from an external voltage supplied through an IO pad to be within the upper tolerable limit of the operating voltage of the IO receiver. The method also includes deriving an output voltage from the first bias voltage during a normal condition and a tolerant condition, and deriving the output voltage from the second bias voltage during a failsafe condition. The tolerant condition is a mode of operation where the external voltage supplied through the IO pad varies from zero to a value higher than the supply voltage, and the failsafe condition is a mode of operation where the supply voltage is zero.

Abstract: A method includes controllably generating a first bias voltage from a supply voltage to be within an upper tolerable limit of an operating voltage of one or more constituent active circuit element(s) of an Input/Output (IO) core device of an integrated circuit (IC) to be interfaced with an IO pad, and controllably generating a second bias voltage from an external voltage supplied through the IO pad to be within the upper tolerable limit of the operating voltage of the one or more constituent active circuit element(s) of the IO core device to be interfaced with the IO pad. The method also includes controllably utilizing a control signal generated by the IO core to derive an output bias voltage from the first bias voltage during a driver mode of operation or the second bias voltage during a failsafe mode of operation and a tolerant mode of operation.

Abstract: Disclosed is a bias circuit with a first resistor connected between the supply voltage and a feedback node. Resistors are connected in series between the feedback node and the reference supply voltage. The connections between the resistors define at least one bias voltage. A second resistor is connected between the feedback node and a first drain node. A first field-effect transistor has a first gate node, the first drain node, and a first source node. The gate node is connected to the first supply voltage. A second field-effect transistor has a second gate node, a second drain node, and a second source node. The second drain node is connected to the first source node. The second gate node is connected to the bias voltage. The second source node is connected to an output signal node. The output signal node capable of experiencing an overshoot voltage.

Abstract: A circuit includes a first comparator block configured to output a voltage equal to a higher of a supply voltage and a bias voltage, a second comparator block configured to output a voltage equal to a higher of the bias voltage and an external voltage supplied through an Input/Output (IO) pad, and a third comparator block configured to output a voltage equal to a higher of the output of the first comparator block and the output of the second comparator block. A voltage across one or more constituent active element(s) of each of the first comparator block, the second comparator block, and the third comparator block is within an upper tolerable limit thereof during each of a normal operation, a failsafe operation, and a tolerant operation.

Abstract: A method includes controllably utilizing a control signal generated by an Input/Output (IO) core to isolate a current path from an external voltage supplied through an IO pad to a supply voltage by transmitting a same voltage at an input terminal of a transistor, configured to be part of a number of cascaded transistors of an IO driver of an interface circuit, to an output terminal thereof during a failsafe mode of operation and a tolerant mode of operation. The method also includes feeding back an appropriate voltage to a floating node created by the isolation of the current path, and controlling a voltage across each transistor of the number of cascaded transistors to be within an upper tolerable limit thereof through an application of a gate voltage to each transistor derived from the supply voltage or the external voltage supplied through the IO pad.

Abstract: A high voltage input receiver using low voltage transistors is disclosed. In one embodiment, an input receiver circuit includes a comparator circuit and an inverter circuit. The comparator circuit includes a differential input module for generating a control signal by comparing an external voltage and a reference voltage, and a decision module for generating an inverter input signal based on the control signal. In addition, the reference voltage is used to set dc trip point of the input receiver. Moreover, the input receiver includes one or more stress protection modules to protect key components of the input receiver from exceeding their reliability limits.

Abstract: A power detect system and circuit for detecting a voltage level of an input/output supply voltage (VDDIO) in a circuit of low voltage devices is disclosed. In one embodiment, the power detect system and circuit includes a voltage divider coupled between the VDDIO and a negative supply voltage (VSS) for generating a bias voltage, a first inverter coupled between a core voltage (VDD) and the VSS for generating a first node voltage based on the bias voltage, a native device coupled between the VDDIO and the VSS for generating a second node voltage based on the bias voltage, and a switch coupled between the first inverter and the native device for controlling the second node voltage based on the first node voltage. The power detect system further includes a second inverter coupled between the VDD and the VSS for generating an output voltage based on the second node voltage.

Abstract: Disclosed are a method, system and apparatus for an improved fail safe I/O driver with pad feedback slew rate control are disclosed. In one embodiment, a pad driver circuit includes a pad node, an NMOS component, a feedback capacitor between the pad node and a gate of the NMOS component to control slew rate across a range of capacitor loads, a switch circuit between the pad node and the feedback capacitor, and a signal generator to generate a signal to control the switch circuit. The switch circuit to maintain a main driver circuit and a pre-driver circuit of the pad driver circuit in a fail safe state when an integrated circuit that includes the pad driver circuit is in the fail safe state. The pad driver circuit may include a PMOS component.

Abstract: A power detect system and circuit for detecting a voltage level of an input/output supply voltage (VDDIO) in a circuit of low voltage devices is disclosed. In one embodiment, the power detect system and circuit includes a voltage divider coupled between the VDDIO and a negative supply voltage (VSS) for generating a bias voltage, a first inverter coupled between a core voltage (VDD) and the VSS for generating a first node voltage based on the bias voltage, a native device coupled between the VDDIO and the VSS for generating a second node voltage based on the bias voltage, and a switch coupled between the first inverter and the native device for controlling the second node voltage based on the first node voltage. The power detect system further includes a second inverter coupled between the VDD and the VSS for generating an output voltage based on the second node voltage.

Abstract: Disclosed is a bias circuit with a first resistor connected between the supply voltage and a feedback node. Resistors are connected in series between the feedback node and the reference supply voltage. The connections between the resistors define at least one bias voltage. A second resistor is connected between the feedback node and a first drain node. A first field-effect transistor has a first gate node, the first drain node, and a first source node. The gate node is connected to the first supply voltage. A second field-effect transistor has a second gate node, a second drain node, and a second source node. The second drain node is connected to the first source node. The second gate node is connected to the bias voltage. The second source node is connected to an output signal node. The output signal node capable of experiencing an overshoot voltage.

Abstract: A high voltage input receiver with hysteresis using low voltage transistors is disclosed. In one embodiment, an input receiver circuit includes a hysteresis comparator circuit, based on a plurality of low voltage transistors, for generating a first output voltage by comparing an external voltage and a reference voltage and a stress protection circuit for preventing the plurality of low voltage transistors of the hysteresis comparator circuit from exceeding their reliability limits. In addition, the reference voltage is used to set a positive trip point and a negative trip point. Moreover, the input receiver circuit includes a source follower circuit for transferring the first output voltage to an output node of the source follower circuit from a voltage level of a VDDIO to a voltage level of a VDD.

Abstract: A high voltage input receiver using low voltage transistors is disclosed. In one embodiment, an input receiver circuit includes a comparator circuit and an inverter circuit. The comparator circuit includes a differential input module for generating a control signal by comparing an external voltage and a reference voltage, and a decision module for generating an inverter input signal based on the control signal. In addition, the reference voltage is used to set dc trip point of the input receiver. Moreover, the input receiver includes one or more stress protection modules to protect key components of the input receiver from exceeding their reliability limits.

Abstract: Circuits and systems including a startup circuit coupled to a reference source for providing startup current to the reference source wherein no transistor of the startup circuit experiences a stress condition and wherein the startup circuit consumes no static current following stabilized, steady-state operation of the reference source.

Abstract: Circuits and systems including a startup circuit coupled to a reference source for providing startup current to the reference source wherein no transistor of the startup circuit experiences a stress condition and wherein the startup circuit consumes no static current following stabilized, steady-state operation of the reference source.