Qualcomm Incorporated

Chulkyu Lee

George Alan Wiley

Shih-Wei Chou

Ying Duan

Shoichiro Sengoku

Dhaval Sejpal

Joseph Cheung

Glenn D Raskin

Harry Huy Dang

Wenjun Su

Le Od Zhang

Ohjoon Kwon

Abhay S Dixit

Shree Krishna Pandey

Jeffrey Charles Lee

Arun Chandra Kundu

Xiang Yang Li

Richard Dominic Wietfeldt

Harikrishna Chintarlapalli Reddy

Sajin Mohamad

Suresh Naidu Lekkala

Guangming Yin

Jonathan Holland

Jae Min Shin

Nakul Midha

Varun Radhakrishnan

Neha Agrawal

Hyunjeong Park

Darshan Chandrashekhar Pande

Le Zhang

Harry Dang

In certain aspects, a voltage regulator includes a pass transistor coupled between an input of the voltage regulator and an output of the voltage regulator, and an amplifier having a first input coupled to a reference voltage, a second input coupled to the output of the voltage regulator via a feedback path, and an output. The voltage regulator also includes a voltage booster coupled between the output of the amplifier and a gate of the pass transistor. In certain aspects, the voltage booster includes a first capacitor and a second capacitor for double charge pumping. In certain aspects, a control circuit of the voltage booster is coupled to a voltage source that is independent of an output voltage of the amplifier.

Charge pump based low dropout regulator

Methods, apparatus, and systems provide improved throughput on a communication link. An apparatus has a plurality of line drivers, a first wire state encoder configured to receive a first symbol in a sequence of symbols when a 3-wire link is in a first signaling state, and to define a second signaling state for the 3-wire link based on the first symbol and the first signaling state, a second wire state encoder configured to receive a second symbol in the sequence of symbols, and to define a third signaling state for the 3-wire link based on the second symbol and the second signaling state. The first symbol immediately precedes the second symbol in the sequence of symbols. The 3-wire link transitions from the first to the second signaling state, and from the second to the third signaling state in consecutive transmission intervals.

C-PHY half-rate wire state encoder and decoder

An apparatus has a plurality of multi-level comparison circuits, each coupled to a pair of wires in a three-wire communication link, a plurality of first-level clock recovery circuits and a second-level clock recovery circuit. Each multi-level comparison circuit provides a multibit signal as an output. Each first-level clock recovery circuit includes a plurality of first-level flipflops clocked by transitions in a multibit signal received from one multi-level comparison circuit of the plurality of multi-level comparison circuits, and a first delay circuit that delays an output of the each first-level clock recovery circuit to provide a first reset signal that resets the each first-level clock recovery circuit. The second-level clock recovery circuit includes a second-level flipflop clocked by transitions in the outputs of the plurality of first-level clock recovery circuits, and a second delay circuit that delays an output of the second-level clock recovery circuit to provide a second reset signal to the second-level flipflop.

Clock and data recovery for multi-phase, multi-level encoding

Methods, apparatus, and systems for communication over a C-PHY interface are disclosed. A transmitting device has a driver circuit configured to drive a three-wire bus in accordance with a symbol received at an input of the driver circuit, a pattern detector receives a sequence of symbols to be transmitted over the three-wire bus in a plurality of transmission symbol intervals, and a selection circuit responsive to a select signal provided by the pattern detector and configured to select between delayed and undelayed versions of a current symbol to drive the input of the driver circuit during a corresponding transmission symbol interval. The select signal may select the delayed version of the current symbol when a combination of the current symbol with an immediately preceding symbol cause the pattern detector to indicate a pattern match.

Unit interval jitter improvement in a C-PHY interface

A termination for a high-frequency transmission line includes a first resistor that has a first terminal coupled to a first end of a transmission line and a second terminal coupled to a first input/output pad, and a second resistor that has a first terminal coupled to the first input/output pad. The first resistor and the second resistor may provide a combined resistance that matches a nominal value of a characteristic impedance of the transmission line. The apparatus may include a third resistor having a first terminal coupled to a second end of a transmission line, and a second terminal coupled to a second input/output pad, and a fourth resistor having a first terminal coupled to the second input/output pad. The third resistor and the fourth resistor may provide a combined resistance that matches the nominal value of the characteristic impedance of the transmission line.

Termination for high-frequency transmission lines

Certain disclosed methods, apparatus, and systems enable improved communication on a multiphase communication link through improved encoding techniques and protocol. A data communication apparatus has a plurality of line drivers configured to couple the apparatus to a 3-wire link, and a data encoder configured to encode at least 3 bits of binary data in each transition between two symbols that are consecutively transmitted by the plurality of line drivers over the 3-wire link such that each pair of consecutively-transmitted symbols comprises two different symbols. Each symbol defines signaling states of the 3-wire link during an associated symbol transmission interval such that each wire of the 3-wire link is in a different signaling state from the other wires of the 3-wire link during the associated symbol transmission interval. Data may be encoded using a combination of 3-phase and pulse amplitude modulation.

Driver architecture for multiphase and amplitude encoding transmitters

An integrated circuit, comprising a transistor-based cell comprising a set of fin field effect transistors (Fin FETs) chained together in a first direction, wherein the set of Fin FETs include fins extending longitudinally along the first direction and equally-spaced apart in a second direction orthogonal to the first direction by a fin pitch, and a set of polysilicon gates extending longitudinally along the second direction and equally-spaced apart in the first direction by a poly pitch, wherein a first dimension of the transistor-based cell along the first direction is substantially a first integer multiplied by the poly pitch, and wherein a second dimension of the transistor-based cell along the second direction is substantially a second integer multiplied by the fin pitch. The integrated circuit may include other non-transistor-based cells (e.g., passive cells), such as thin-film resistor or capacitor cells, which are arranged in a two-dimensional array with the transistor-based cell.

Analog-mixed signal circuit cells with universal Fin pitch and poly pitch

System, methods and apparatus are described that facilitate transmission of data, particularly between two devices within electronic equipment. Transmission lines are selectively terminated in an N-phase polarity encoded transmitter when the transmission lines would otherwise be undriven. Data is mapped to a sequence of symbols to be transmitted on a plurality of wires. The sequence of symbols is encoded in three signals. A first terminal of a plurality of terminals may be driven such that transistors are activated to couple the first terminal to first and second voltage levels. The first terminal may further be driven such that a dedicated transistor is activated to couple the first terminal to an intermediate voltage level.

Low power physical layer driver topologies

Methods, apparatus, and systems for data communication over a multi-wire, multi-phase interface are disclosed. A method includes equalizing three-phase signals received from two wires of the interface to provide equalized signals, providing first and second difference signals by comparing voltage differences between the equalized signals with first and second reference voltage levels respectively, capturing delayed and undelayed versions of the second difference signal using flipflops triggered by different edges in the first difference signal, and adjusting an equalizing circuit until outputs of the first flipflops indicate that a ratio of low-frequency attenuation to high-frequency amplification has been achieved that enables information to be accurately decoded from the three-phase signals. The three-phase signal received from a first of the two wires is in a different phase than the three-phase signal received from a second of the two wires.

C-PHY receiver equalization

A receiver amplifier and also a receiver equalizer is provided for a three-level signaling system. The receiver amplifier includes a single current source that drives a current into node shared by three transistors arranged in parallel. A trio of input signals corresponds to the three transistors on a one-to-one basis. Each input signal drives the gate of its corresponding transistor. In addition, each transistor produces a corresponding output voltage at a terminal coupled to a resistor. The receiver equalizer includes three transistors and three corresponding equalizing pairs of a resistor and a capacitor. A terminal for the capacitor and for the resistor in each equalizing pair connects to a terminal of the corresponding transistor.

Three-input continuous-time amplifier and equalizer for multi-level signaling

Methods, apparatus, and systems for calibration and correction of data communications over a multi-wire, multi-phase interface are disclosed. In particular, calibration is provided for data communication devices coupled to a 3-line interface. The calibration includes generating and transmitting a calibration pattern on the 3-line interface, where the generation of the pattern includes toggling two of three interface lines from one voltage level to another voltage level over a predetermined time interval. Furthermore, the generation of the pattern includes maintaining a remaining third interface line at a common mode voltage level over the predetermined time interval, wherein only a single transition occurs for the predetermined time interval. Calibration data may then be derived in a receiver device using the transmitted calibration pattern.

Calibration pattern and duty-cycle distortion correction for clock data recovery in a multi-wire, multi-phase interface

Data communication apparatus and methods for a multi-wire interface are disclosed. A half rate clock and data recovery (CDR) circuit derives a clock signal including pulses corresponding to symbols transmitted on a 3-wire interface, where the symbols are transmitted at a particular frequency with each of the symbols occurring over a unit interval (UI) time period. The first clock signal is input to a flip-flop logic included in a delay loop, and serves to trigger the first flip-flop logic. A second clock signal is generated using a programmable generator in the delay loop and has a frequency of a half UI and is fed back to a data input of the flip-flop. The output of the flip-flop is used as a recovered clock signal for the CDR at a half rate frequency. This design provides ease of timing control, a delay line without extra nonlinear-effects, and less hardware overhead.

Multiphase clock data recovery with adaptive tracking for a multi-wire, multi-phase interface

A method for error detection in transmissions on a multi-wire interface includes providing a plurality of launch clock signals, including launch clock signals having a different phase shifts, determining a type of transition in signaling state that will occur on each wire of the 3-wire interface at a boundary between two consecutively transmitted symbols, and selecting one of the plurality of launch clock signals to initiate the transition of signaling state on each wire of the 3-phase interface. Selecting one of the plurality of launch clock signals may include selecting a first launch clock signal when the transition in signaling state terminates at an undriven state, and selecting a second launch clock signal when the transition in signaling state begins at an undriven state. An edge in the first launch clock signal may occur before a corresponding edge in the second launch clock signal.

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San Diego, CA, United States of America

Chulkyu Lee