Patents by Inventor Taisheng An

Taisheng An 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).

  • Patent number: 5546355
    Abstract: An integrated circuit memory (20) has a write pulse generator (38) for generating a self-timed write pulse independent of system clock frequency and system clock duty cycle. The write pulse generator (38) includes a delay element (56) and a delay element (68). The write pulse is triggered on a rising edge of the clock signal and has a duration that is determined by a delay time provided by the delay element (68). The delay elements (56, 68) provide single-sided delays and compensate for process, power supply, temperature variations of the integrated circuit memory (20).
    Type: Grant
    Filed: February 24, 1995
    Date of Patent: August 13, 1996
    Assignee: Motorola, Inc.
    Inventors: Donovan L. Raatz, Taisheng Feng
  • Patent number: 5497347
    Abstract: A cache TAG comparator (20) has a combined data multiplexer and compare circuit (30) for multiplexing redundant columns (26) with normal columns of memory cells and for comparing input data with a TAG address stored in a TAG array (21) for determining if data required by a data processing system is located in a corresponding cache memory. A BICMOS match logic circuit (40) receives a compare signal from each data multiplexer and compare circuit, and provides a logic high match signal indicating a cache hit in response to a logic state of the input data and the TAG address being identical. The comparison is performed in ECL, allowing high speed operation. Also, the match signal is generated prior to a critical read path, insuring faster generation of the match signal.
    Type: Grant
    Filed: June 21, 1994
    Date of Patent: March 5, 1996
    Assignee: Motorola Inc.
    Inventor: Taisheng Feng
  • Patent number: 5497106
    Abstract: A BICMOS output buffer circuit (20) has a voltage converter (21), a reference voltage circuit (28), a driver circuit (24), and a clamping circuit (40). The reference voltage circuit (28) receives a regulated voltage and provides a reference voltage having a low voltage level and a high voltage level. The low voltage level and the high voltage level control the logic high voltage of an output data signal. During a transition from a logic low voltage to a logic high voltage of the output data signal, the output data signal is allowed to overshoot the low voltage level. After the transition is complete, the output data signal settles at the high voltage level. This limits the amount of overshoot of the output data signal. The clamping circuit (40) dampens the oscillations of the output signal.
    Type: Grant
    Filed: September 19, 1994
    Date of Patent: March 5, 1996
    Assignee: Motorola Inc.
    Inventors: Donovan Raatz, Taisheng Feng, Alan R. Bormann
  • Patent number: 5293081
    Abstract: A driver circuit (33) for output buffers or the like provides differing switching speed and di/dt depending on whether an output signal is switched in response to input signals or a control signal.
    Type: Grant
    Filed: September 28, 1992
    Date of Patent: March 8, 1994
    Assignee: Motorola, Inc.
    Inventors: Jennifer Y. Chiao, Stephen Flannagan, Taisheng Feng
  • Patent number: 5291455
    Abstract: A memory (20) has N.sub.BIAS generators (63 and 73) coupled to the positive and negative power supply lines (61 and 62) at a point close to amplifiers (84 and 85) and address buffers (76) to insure that they all receive the same power supply voltage to prevent an impact on the access times of memory (20). A V.sub.CS generator (65) is located close to power supply bonding pads (23 and 25) and to output buffers (77 and 78) to reduce the effects of power supply line noise on the noise margins. A V.sub.AREF generator provides a reference voltage to the differential amplifiers of address buffers (75 and 76). Locating V.sub.AREF generator (67) close to power supply bonding pads (23 and 25) insures that the reference voltage is always at the midpoint of the input logic swing.
    Type: Grant
    Filed: May 8, 1992
    Date of Patent: March 1, 1994
    Assignee: Motorola, Inc.
    Inventors: Taisheng Feng, John D. Porter, Jennifer Y. Chiao
  • Patent number: 5287314
    Abstract: A memory (50) having a BICMOS sense amplifier (20) includes a differential amplifier stage (11), emitter-follower input transistors (25 and 26), and emitter-follower output transistors (27 and 28). When sense amplifier (20) is deselected, P-channel transistors (31-37) pull the bases of the bipolar transistors (23-28) to V.sub.DD -2V.sub.BE and P-channel transistors (29 and 30) decouple the bases of emitter-follower output transistors (27 and 28) from the collectors of transistors (23 and 24). At the same time, N-channel transistors (38, 40, 42, 44, and 46) decouple N-channel transistors (39, 41, 43, 45, and 47) from the emitters of bipolar transistors (23-28). Thus, no current can flow, reducing the power consumption of sense amplifier (20). Also, bipolar transistors (23-28) are prevented from being excessively reverse-biased. Additionally, a plurality of sense amplifiers (20) can have their outputs wired-OR connected.
    Type: Grant
    Filed: May 26, 1992
    Date of Patent: February 15, 1994
    Assignee: Motorola, Inc.
    Inventors: Stephen T. Flannagan, Taisheng Feng
  • Patent number: 5184033
    Abstract: A regulated BiCMOS output buffer (34) regulates a logic high voltage of an output signal to improve interfacing to loads such as 3.3 volt integrated circuits. The output buffer (34) provides a first voltage to a base of a pullup transistor (116) in response to a difference between an input voltage and a reference voltage. An emitter of the pullup transistor (116) provides an output signal. A second transistor (102) having characteristics matching those of the pullup transistor (116) receives the first voltage at its base, and provides the input voltage at its emitter. The output buffer (34) changes the first voltage until the voltage at the base of the second transistor (102) equals the reference voltage. Thus, signal reflections on the output signal do not affect the performance of the output buffer. Clamps (99, 120) coupled to the base and emitter of the pullup transistor (116) provide soft clamping according to a square law.
    Type: Grant
    Filed: September 20, 1991
    Date of Patent: February 2, 1993
    Assignee: Motorola, Inc.
    Inventors: Jennifer Y. Chiao, Stephen Flannagan, Taisheng Feng
  • Patent number: 5043943
    Abstract: A parity SRAM having the capability to support byte parity is provided. The parity SRAM uses four (4) independent byte write enable (BWE.sub.x) signals to enable a write amplifier to individually write a single parity bit to a selected memory location. The SRAM is designed to function in either a parity or a non-parity mode. A bonding option pad is connected to parity control logic circuitry, and determines whether the SRAM will function in the parity mode or the non-parity mode. The parity control logic circuitry generates a parity signal, based on the electrical connection of the option pad. Thus, when the option pad is connected to ground, the parity option is selected, whereas, when the option pad is connected to a positive power supply, then non-parity functionality is selected. When parity functionality is selected, the the SRAM will allow the four (4) independent BWE.sub.x signals to individually enable the write amplifier.
    Type: Grant
    Filed: June 18, 1990
    Date of Patent: August 27, 1991
    Assignee: Motorola, Inc.
    Inventors: Richard D. Crisp, Taisheng Feng, Jennifer Y. Chiao
  • Patent number: 4958086
    Abstract: An output buffer in an integrated circuit comprising voltage regulator, a predriver, and an output stage. The integrated circuit comprises a chip and a package and interconnections therebetween. The voltage regulator is coupled to a first power supply voltage terminal and a second power supply voltage terminal, and provides a regulated voltage signal characterized as having a constant voltage substantially independent of fluctuations in voltage between the first power supply voltage terminal and the second power supply voltage terminal. The predriver receives the regulated voltage signal and a data input signal and provides a regulated predriven signal in response to the data signal. The output stage receives the regulated predriven signal and provides an output signal in response thereto. The output signal is driven onto a bonding pad of the device to provide an interconnection point between the chip and the package.
    Type: Grant
    Filed: May 8, 1989
    Date of Patent: September 18, 1990
    Assignee: Motorola, Inc.
    Inventors: Karl L. Wang, Taisheng Feng