Patents by Inventor Zhihong CHENG

Zhihong CHENG has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20180138903
    Abstract: A CMOS buffer circuit includes a first branch circuit having first and second transistors connected in parallel between a voltage source and ground, and a second branch having third and fourth transistors connected in parallel between the voltage source and ground. The gates of the first and second transistors receive an input signal. The gates of the third and fourth transistors are connected to a first node between the drains of the first and second transistors. An output signal is provided at a second node between the drains of the third and fourth transistors. The first and fourth transistors have conductive channels of a first type, and the second and third transistors have conductive channels of a second type that is different from the first type. In one embodiment, the first and fourth transistors are high threshold voltage transistors and the second and third transistors are low threshold voltage transistors.
    Type: Application
    Filed: August 16, 2017
    Publication date: May 17, 2018
    Inventor: Zhihong Cheng
  • Patent number: 9946597
    Abstract: Electromagnetic compatibility (EMC) of a system-on-a-chip (SoC) is enhanced by encoding at least a subset of control signals before the control signals are transmitted over a bus (e.g., a bus internal to a SoC) from a controller to an embedded nonvolatile memory (NVM). The error-detection code used causes an EMC event to introduce errors into the transmitted codewords with relatively high probability. In response to an error being detected in the transmitted codeword, a set of safeguarding operations are performed to prevent the data stored in the NVM from being uncontrollably changed.
    Type: Grant
    Filed: September 4, 2016
    Date of Patent: April 17, 2018
    Assignee: NXP USA, INC.
    Inventors: Zhihong Cheng, Yin Guo
  • Patent number: 9893771
    Abstract: A frequency shift keying (FSK) demodulation component having of a sampler that receives an FSK modulated signal, samples the received FSK modulated signal, and outputs the sampled signal. The FSK demodulation component further includes a low pass filter that filters the sampled signal, and a frequency shift detector that detects shifts in frequency of the low pass filtered sampled signal. The FSK demodulation component then outputs an indication of the detection of shifts in frequency of the low pass filtered sampled signal.
    Type: Grant
    Filed: August 11, 2016
    Date of Patent: February 13, 2018
    Assignee: NXP USA, INC.
    Inventors: Zhiling Sui, Zhijun Chen, Zhihong Cheng, SHixiang Nie
  • Patent number: 9755623
    Abstract: A multi-bit flip-flop has first and second one-bit flip-flops. The multi-bit flip-flop employs inter-cell clock switch (CSW) sharing in which the first and second one-bit flip-flops share at least one clock switch. The multi-bit flip-flop may also employ intra-cell CSW sharing in which at least one of the first and second one-bit flip-flops shares at least one clock switch. The inter-cell CSW sharing enables implementation of multi-bit flip-flops with fewer clock switches and possibly fewer data devices, while reducing power consumption, including state retention power gating power reduction.
    Type: Grant
    Filed: August 7, 2016
    Date of Patent: September 5, 2017
    Assignee: NXP USA, INC.
    Inventors: Zhihong Cheng, Peidong Wang, Yang Wang
  • Patent number: 9660849
    Abstract: A method of demodulating an FSK modulated input signal whose frequency varies between first and second frequencies. The input signal is delayed by a plurality of cycles, providing a second signal. A succession of phase reference signals having respective incrementally greater phase delays relative to the input signal are provided. Samples of the phase reference signals are taken at intervals determined by the second signal. A transition between the first and second frequencies is detected when the relative values of the samples of the phase reference signals remain constant during a plurality of intervals after varying. A high speed clock is not required to perform the demodulation.
    Type: Grant
    Filed: September 28, 2015
    Date of Patent: May 23, 2017
    Assignee: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Zhiling Sui, Zhijun Chen, Zhihong Cheng, Jiangtao Pan
  • Publication number: 20170139772
    Abstract: Electromagnetic compatibility (EMC) of a system-on-a-chip (SoC) is enhanced by encoding at least a subset of control signals before the control signals are transmitted over a bus (e.g., a bus internal to a SoC) from a controller to an embedded nonvolatile memory (NVM). The error-detection code used causes an EMC event to introduce errors into the transmitted codewords with relatively high probability. In response to an error being detected in the transmitted codeword, a set of safeguarding operations are performed to prevent the data stored in the NVM from being uncontrollably changed.
    Type: Application
    Filed: September 4, 2016
    Publication date: May 18, 2017
    Inventors: Zhihong Cheng, Yin Guo
  • Publication number: 20170116365
    Abstract: An integrated circuit (IC) has a block of instances of cells aligned in rows of at least first and second heights. The instances of cells are selected from at least two different libraries of standard cells that have heights that are integer multiples of the first and second heights respectively as a function of performance criteria of the instances of cells. The floorplan provides respective numbers of rows of the different heights as a function of the ratios of the total widths of rows of the different heights needed to place the selected standard cells.
    Type: Application
    Filed: September 4, 2016
    Publication date: April 27, 2017
    Inventors: ZHIHONG CHENG, Yifeng Liu, Peidong Wang
  • Publication number: 20170070265
    Abstract: A frequency shift keying (FSK) demodulation component having of a sampler that receives an FSK modulated signal, samples the received FSK modulated signal, and outputs the sampled signal. The FSK demodulation component further includes a low pass filter that filters the sampled signal, and a frequency shift detector that detects shifts in frequency of the low pass filtered sampled signal. The FSK demodulation component then outputs an indication of the detection of shifts in frequency of the low pass filtered sampled signal.
    Type: Application
    Filed: August 11, 2016
    Publication date: March 9, 2017
    Inventors: ZHILING SUI, Zhijun CHEN, Zhihong CHENG, Shixiang NIE
  • Publication number: 20170063350
    Abstract: A multi-bit flip-flop has first and second one-bit flip-flops. The multi-bit flip-flop employs inter-cell clock switch (CSW) sharing in which the first and second one-bit flip-flops share at least one clock switch. The multi-bit flip-flop may also employ intra-cell CSW sharing in which at least one of the first and second one-bit flip-flops shares at least one clock switch. The inter-cell CSW sharing enables implementation of multi-bit flip-flops with fewer clock switches and possibly fewer data devices, while reducing power consumption, including state retention power gating power reduction.
    Type: Application
    Filed: August 7, 2016
    Publication date: March 2, 2017
    Inventors: ZHIHONG CHENG, PEIDONG WANG, YANG WANG
  • Patent number: 9490789
    Abstract: A clock switching circuit includes first and second clock lines, first and second selection lines, and first through fourth Muller C-elements. The Muller C-elements are connected to the clock and selection lines and first and second logic gates. First and second delay cells are connected to the clock lines and the second and fourth Muller C-elements. A first AND gate is connected to the first clock line, the first Muller C-element, and the first delay cell. A second AND gate is connected to the second delay cell, the third Muller C-element, and the second clock line, and an OR gate is connected to the first and second AND gates.
    Type: Grant
    Filed: April 27, 2016
    Date of Patent: November 8, 2016
    Assignee: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Chaoxuan Tian, Zhihong Cheng, Zhiling Sui
  • Publication number: 20160285658
    Abstract: A method of demodulating an FSK modulated input signal whose frequency varies between first and second frequencies. The input signal is delayed by a plurality of cycles, providing a second signal. A succession of phase reference signals having respective incrementally greater phase delays relative to the input signal are provided. Samples of the phase reference signals are taken at intervals determined by the second signal. A transition between the first and second frequencies is detected when the relative values of the samples of the phase reference signals remain constant during a plurality of intervals after varying. A high speed clock is not required to perform the demodulation.
    Type: Application
    Filed: September 28, 2015
    Publication date: September 29, 2016
    Inventors: Zhiling Sui, Zhijun Chen, Zhihong Cheng, Jiangtao Pan
  • Patent number: 9191021
    Abstract: A pipelined analog-to-digital converter (ADC) that converts an analog input voltage signal Vin into a digital output value Dout. The ADC has a sequence of stages including a first calibrated stage having: (1) an ADC sub-module that receives Vin and provides an ADC sub-module digital output value based on Vin, (2) a DAC sub-module that receives the ADC sub-module digital output value and outputs a corresponding analog voltage signal VDAC, (3) a first difference module that generates an analog residual-voltage signal based on a difference between Vin and VDAC, and (4) an artificial-noise-insertion module that inserts an analog artificial-noise voltage signal into the residual voltage signal to generate an analog combined voltage signal. The analog combined voltage signal is used to calibrate the first calibrated stage. The artificial-noise-insertion module generates the polarity of the artificial-noise voltage signal based on the polarity of the corresponding residual voltage signal.
    Type: Grant
    Filed: April 26, 2015
    Date of Patent: November 17, 2015
    Assignee: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Zhiling Sui, Zhijun Chen, Zhihong Cheng, Yanping Zhang
  • Patent number: 9166585
    Abstract: A low power inverter circuit includes first and second transistors that receive an input signal at their gate terminals. The first and second transistors are connected by way of their source terminals to third and fourth transistors, respectively. The third and fourth transistors are connected in parallel with fifth and sixth transistors, respectively. The third and fourth transistors are continuously switched on, and the fifth and sixth transistors are controlled in such a way to reduce short circuit current flowing through the first and second transistors when the input signal transitions from one state to another.
    Type: Grant
    Filed: August 20, 2014
    Date of Patent: October 20, 2015
    Assignee: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Amit Roy, Zhihong Cheng, Amit Kumar Dey, Vijay Tayal, Chetan Verma
  • Patent number: 9148149
    Abstract: A latch circuit has a tri-state gate and a reverse tri-state gate that share the same complementary controls. The reverse tri-state gate locks an output of the tri-state gate when the tri-state gate is shut-off. The complementary control signals include a first undoped polysilicon strip. The output of the reverse tri-state gate may be coupled to the output of the tri-state gate via a second undoped polysilicon strip.
    Type: Grant
    Filed: February 7, 2014
    Date of Patent: September 29, 2015
    Assignee: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Zhihong Cheng, Peidong Wang
  • Publication number: 20150102839
    Abstract: A low power inverter circuit includes first and second transistors that receive an input signal at their gate terminals. The first and second transistors are connected by way of their source terminals to third and fourth transistors, respectively. The third and fourth transistors are connected in parallel with fifth and sixth transistors, respectively. The third and fourth transistors are continuously switched on, and the fifth and sixth transistors are controlled in such a way to reduce short circuit current flowing through the first and second transistors when the input signal transitions from one state to another.
    Type: Application
    Filed: August 20, 2014
    Publication date: April 16, 2015
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Amit Roy, Zhihong Cheng, Amit Kumar Dey, Vijay Tayal, Chetan Verma
  • Publication number: 20150091626
    Abstract: A state retention power gated cell includes a logic cell arranged in two or more rows. The logic cell has an active layer including at least a first well and a second well disposed in first and second rows, respectively. In a normal operation mode, the first well is powered with a first bias voltage, the second well is powered with a second bias voltage, the first power supply line is powered with VDDC, and the second power supply line is powered with VDD. In a standby mode, the first well preferably is powered down, the second well is powered with the second bias voltage, the first power supply line is powered with VDDC, and the second power supply line is powered down.
    Type: Application
    Filed: May 15, 2014
    Publication date: April 2, 2015
    Inventors: Miaolin Tan, Zhihong Cheng, Juan Fu, Peidong Wang, Yali Wang
  • Publication number: 20150084680
    Abstract: A state retention power gated (SRPG) cell includes a retention circuit coupled to a power gated circuit. The retention circuit stores state information of the power gated circuit before a low power period is started. A gated power supply coupled to the power gated circuit and to a first end of a power supply switch supplies a gated supply voltage to the power gated circuit during a non-low power period. A local power supply coupled to the retention circuit and to a second end of the power supply switch is coupled to the gated power supply in the non-low power period, and a non-gated power supply is coupled to the local power supply via an isolation element to isolate the non-gated power supply from the local power supply during the non-low power period, and to couple the non-gated power supply to the local power supply during the low power period.
    Type: Application
    Filed: February 26, 2014
    Publication date: March 26, 2015
    Inventors: Zhihong Cheng, Zhijun Chen, Huabin Du, Peidong Wang, Shayan Zhang
  • Patent number: 8987786
    Abstract: A state retention power gated cell includes a logic cell arranged in two or more rows. The logic cell has an active layer including at least a first well and a second well disposed in first and second rows, respectively. In a normal operation mode, the first well is powered with a first bias voltage, the second well is powered with a second bias voltage, the first power supply line is powered with VDDC, and the second power supply line is powered with VDD. In a standby mode, the first well preferably is powered down, the second well is powered with the second bias voltage, the first power supply line is powered with VDDC, and the second power supply line is powered down.
    Type: Grant
    Filed: May 15, 2014
    Date of Patent: March 24, 2015
    Assignee: Freescale Semiconductor, Inc
    Inventors: Miaolin Tan, Zhihong Cheng, Juan Fu, Peidong Wang, Yali Wang
  • Patent number: 8941429
    Abstract: In a master-slave flip-flop, the master latch has first and second three-state stages, and a first feedback stage. The slave latch has third and fourth three-state stages, and a second feedback stage. First and second clock switches having opposite phases are provided. The first clock switch is configured in one of the first and fourth three-state stages, and the other stage shares the first clock switch. The second clock switch is configured in one of the second and third three-state stages, and the other stage shares the second clock switch. The second three-state stage has an additional pair of complementary devices having signal paths connected in series with each other with both being gated by a data output of the slave latch. The flip-flop reduces the number of clock switches and clock switch power consumption.
    Type: Grant
    Filed: August 6, 2013
    Date of Patent: January 27, 2015
    Assignee: Freescale Semiconductor, Inc.
    Inventor: Zhihong Cheng
  • Patent number: 8884669
    Abstract: An electronic device has a power control module for causing selected functional blocks to run in a low power mode of operation, while leaving other functional blocks supplied continuously with power. A power mode control distribution network includes serially connected chains of buffers in a distribution tree for distributing power mode control signals received at a common input end to respective output ends which are connected to respective functional blocks. In the low power mode of operation the power control module causes power to be supplied continuously to output buffers at the output ends of the chains while causing power supplied to other buffers to be reduced or cut-off. The output buffers include feedback paths for causing the states of the output buffers prior to the low power mode of operation to latch during the low power mode of operation.
    Type: Grant
    Filed: August 12, 2013
    Date of Patent: November 11, 2014
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Xiaoxiang Geng, Zhihong Cheng, Huabin Du, Miaolin Tan