Qualcomm Incorporated

Ashwin Sethuram

Satish Krishnamoorthy

Young Uk Yim

Mostafa Naguib Abdulla

Chang Ki Kwon

Jacob Schneider

Prince Mathew

Jeffrey Mark Hinrichs

Patrick Isakanian

Michael Thomas Fertsch

Mohammed Mizanur Rahman

Andrew Tohmc

Gurmukh Singh

Seokkyun Ko

Jaseem Ahammed

Levon Msryan

Tigran Melikyan

Changkyo Lee

An ESD protection circuit in an interface circuit has a first diode coupled between a first power source of an integrated circuit device and an input/output pad of the integrated circuit device, a second diode coupled between a second power source of the integrated circuit device and the input/output pad, and a resistive element that couples the second diode to the first diode and to the input/output pad. The first power source supplies a driver circuit coupled to the input/output pad. The second power source supplies one or more core circuits of the integrated circuit device. The resistive element may be implemented as an interconnect configured to provide a resistance that produces a voltage differential between a terminal of the second diode and a corresponding terminal of the first diode during an electrostatic discharge event.

Electrostatic discharge circuit for multi-voltage rail thin-gate output driver

An ESD protection circuit in an interface circuit has a first diode coupled between a power source of an integrated circuit device and an input/output pad of the integrated circuit device, a second diode coupled between a first terminal of a first resistive element and the input/output pad, with a second terminal of the first resistive element being coupled to the power source, a second resistive element that couples the second diode to the first diode and to the input/output pad; a first clamping circuit coupled between the power source and a ground reference of the integrated circuit device, and a second clamping circuit coupled between the first terminal of the first resistive element and the ground reference. The power source supplies a driver circuit coupled to the input/output pad.

Electrostatic discharge robustness for a single rail transmitting driver

A data signal receiver circuit, including: a comparator configured to generate a first data signal based on a comparison of an input data signal and a reference voltage, wherein the first data signal includes a first logic low pulse and a first logic high pulse; and a duty cycle control circuit configured to generate: a second data signal based on the first data signal, wherein the second data signal includes a second logic low pulse responsive to the first logic low pulse, wherein the second logic low pulse has a width greater than a unit interval (UI); and a third data signal based on the first data signal, wherein the third data signal includes a second logic high pulse responsive to the first logic high pulse, wherein the second logic high pulse has a width greater than the UL.

Data receiver circuit including loop-unrolled phase decision feedback equalizer with duty cycle control

A reconfigurable driver in an I/O circuit has a first transistor provided in a first pullup structure, a second transistor provided in a second pullup structure, and a control circuit that generates a control signal provided to a gate of the second transistor. A gate of the first transistor receives a data signal. The control signal is an inverted, delayed version of the data signal in a first mode. The control signal turns off the second transistor in a second mode. The control circuit generates the control signal using a version of the data signal when operated in a third mode. The second pullup structure may be used to provide one-shot equalization to an output of the reconfigurable driver when the second pullup structure is operated in the first mode. The second transistor may be a thin-oxide PMOS transistor. The first transistor may be a thin-oxide NMOS transistor.

Double data rate output circuit with reconfigurable equalizer

A transmitter circuit includes a first driver circuit configured to drive an input/output pad in an integrated circuit device, the first driver circuit including a thin-oxide transistor configured to couple the input/output pad to a first voltage rail when the transmitter circuit is operated in a first mode; a gate pullup transistor configured to couple a gate of the thin-oxide transistor to a second voltage rail when voltage of a third voltage rail is collapsed to a zero-volt level; and a switch configured to block transmission of a gating signal to the gate of the thin-oxide transistor when the voltage of the third voltage rail is collapsed to the zero-volt level.

DDR PHY power collapse circuit for multimode double data rate synchronous dynamic random access memory

A transmitter includes a pull-down circuit coupled between an output of the transmitter and a first rail, a first pull-up circuit coupled between a second rail and the output of the transmitter, and a second pull-up circuit coupled between the second rail and the output of the transmitter. The transmitter also includes a control circuit coupled to a control input of the first pull-up circuit and a control input of the second pull-up circuit. The control circuit is configured to output a first control signal to the control input of the first pull-up circuit, wherein the first control signal controls a drive strength of the first pull-up circuit. The control circuit is also configured to output a second control signal to the control input of the second pull-up circuit, wherein the second control signal controls a drive strength of the second pull-up circuit.

Hybrid transmitter with calibration

A delay element including a first set of field effect transistors (FETs) with gates configured to receive a first control voltage; a second set of FETs coupled in series with the first set of FETs between a first voltage rail and a first node, respectively, the second set of FETs include gates configured to receive a set of complementary select signals, respectively; a third set of FETs including gates configured to receive a set of non-complementary select signals, respectively; a fourth set of FETs coupled in series with the third set of FETs between a second node and a second voltage rail, respectively, the fourth set of FETs including gates configured to receive a second control voltage; and an inverter coupled between the first node and the second node, the inverter including an input configured to receive an input signal and an output configured to produce an output signal.

Inverter-based delay element with adjustable current source/sink to reduce delay sensitivity to process and supply voltage variation

Certain aspects of the present disclosure provide methods and apparatus for equalizing a transmitter circuit for use in high-speed data links, such as in a serializer/deserializer (SerDes) scheme. One example transmitter circuit generally includes at least one driver stage, a first equalization circuit coupled to an output of the transmitter circuit, and a second equalization circuit coupled to an input of the at least one driver stage. One example method of transmitting data generally includes operating a transmit circuit comprising: at least one driver stage, a first equalization circuit coupled to an output of the transmitter circuit, and a second equalization circuit coupled to an input of the at least one driver stage; and selectively enabling at least one of the first equalization circuit or the second equalization circuit.

Equalization for a transmitter circuit

A hybrid output data path is provided that supports high-voltage signaling and low-voltage signaling. The high-voltage signaling is powered by a high-power supply voltage that is greater than a low-power supply voltage that powers the low-voltage signaling.

High-voltage and low-voltage data paths of a hybrid output driver

A hybrid output driver is disclosed that supports high-voltage signaling and low-voltage signaling. The high-voltage signaling is powered by a high-power supply voltage that is greater than a low-power supply voltage that powers the low-voltage signaling.

Growing community of inventors

San Clemente, CA, United States of America

Ashwin Sethuram