Patents Assigned to Elite Semiconductor Memory
  • Patent number: 8773186
    Abstract: A duty cycle correction circuit comprises a duty cycle detector, a filter, a comparator, a SAR DAC, an equalization device, a pass gate circuit, and a duty cycle corrector. The duty cycle detector generates control signals in response to internal clock signals. The equalization device equalizes voltage levels of the control signals, and the pass gate circuit applies the control signals to the duty cycle corrector. The filter obtains average voltages of the control signals. The comparator compares output signals from the filter to generate a comparison result. The SAR DAC performs a SAR algorithm to generate analog output signals based on the comparison result. The duty cycle corrector receives external clock signals, the analog output signals, and output signals from the pass gate circuit to generate the internal clock signals with a corrected duty cycle.
    Type: Grant
    Filed: August 1, 2013
    Date of Patent: July 8, 2014
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventors: Jian-Sing Liou, Shu-Han Nien
  • Patent number: 8698479
    Abstract: A bandgap reference circuit includes a first circuit, a second circuit and a third circuit. The first circuit is for generating a first current and a first voltage according to a first reference voltage. The second circuit is coupled to the first circuit, for generating a second voltage according to the first voltage. The third circuit is coupled to the first circuit and the second circuit, for generating a voltage offset according to the first current, and generating a bandgap reference voltage according to the second voltage and the voltage offset. The first circuit and the second circuit complement each other for offsetting variations of the bandgap reference voltage due to temperature changes.
    Type: Grant
    Filed: March 30, 2012
    Date of Patent: April 15, 2014
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventor: Ming-Sheng Tung
  • Patent number: 8649236
    Abstract: A circuit for controlling leakage current in random access memory devices comprises a pre-charge equalization circuit. The pre-charge equalization circuit provides a pre-charge voltage to a pair of complementary bit lines of a memory cell of a random access memory device in accordance with a pre-charge signal. When the memory cell is in a self-refresh mode, the pre-charge signal is activated by a periodically triggered pre-charge request and also activated before and after the memory cell is self-refreshed.
    Type: Grant
    Filed: May 11, 2011
    Date of Patent: February 11, 2014
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventors: Chung Zen Chen, Ying Wei Jan, Jian Shiang Liang
  • Patent number: 8599633
    Abstract: A semiconductor memory device includes memory cells, a sensing amplifier, a precharge circuit, and a control signal generator. The precharge circuit has a NMOS transistor and two PMOS transistors, and is used to precharge bit lines of a bit line pair, wherein the NMOS transistor is controlled by a first control signal, and the two PMOS transistors are controlled by a second control signal. The control signal generator is used to generate the first and second control signals, wherein the first control signal is at a logic high level only when the second control signal is at a first logic low level, the first control signal is at a logic low level when the second control signal is at a second logic low or a first logic high level, and the second logic low level is higher than the first logic low level.
    Type: Grant
    Filed: May 6, 2012
    Date of Patent: December 3, 2013
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventor: Ming-Sheng Tung
  • Patent number: 8581560
    Abstract: A voltage regulator circuit comprises active and standby amplifiers, first and second transistors, and a capacitor. The active amplifier has a negative input connected to a first reference voltage, and the standby amplifier has a negative input connected to a second reference voltage. The first reference voltage is greater than the second reference voltage. The first transistor has a gate connected to an output of the active amplifier and a drain connected to a voltage regulated output, and the second transistor has a gate connected to an output of the standby amplifier and a drain connected to the voltage regulated output. The capacitor is connected between a chip enable signal and the voltage regulated output.
    Type: Grant
    Filed: July 1, 2010
    Date of Patent: November 12, 2013
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventor: Chung-Zen Chen
  • Patent number: 8575912
    Abstract: The present invention discloses a circuit for generating a dual-mode proportional to absolute temperature (PTAT) current. The circuit includes a voltage stabilizing circuit to provide a voltage reference, and a load current control circuit comprising a first transistor to provide a first load current based on the voltage reference, a second transistor to provide a second load current based on the voltage reference, a first switch to control whether to allow the first load current to flow therethrough in response to different predetermined temperatures, and a second switch to control whether to allow the second load current to flow therethrough in response to the different predetermined temperatures. A resultant current resulting from at least one of the first load current or the second load current has different current magnitudes at the different predetermined temperatures.
    Type: Grant
    Filed: May 21, 2012
    Date of Patent: November 5, 2013
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventor: Ming-Sheng Tung
  • Patent number: 8570817
    Abstract: A data input device for use in a memory device to avoid false data being written due to a postamble ringing phenomenon in a write operation is provided. The data input device comprises a buffer, a combinational logic circuit and a flip-flop unit. The buffer receives the data and outputs internal data to the flip-flop unit. The combinational logic circuit receives an external data strobe signal to generate a first data strobe signal and a second data strobe signal. The flip-flop unit stores the data in synchronization with the first data strobe signal and outputs the stored data in synchronization with the second data strobe signal. A last rising edge of the second data strobe signal is generated prior to onset of the postamble ringing on the external data strobe signal, so that a data transferred path in the flip-flop unit is closed prior to onset of the postamble ringing.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: October 29, 2013
    Assignee: Elite Semiconductor Memory Technology, Inc.
    Inventor: Ming-Chien Huang
  • Patent number: 8565040
    Abstract: A voltage regulator circuit for providing power management for a memory device is disclosed. The voltage regulator circuit comprises a voltage regulator and a switch circuit. The switch circuit includes a first oscillator to generate an oscillating signal, and a pulse generator to generate a pulse signal in response to the oscillating signal. The voltage regulator provides a current during standby mode of the memory device in response to the pulse signal. The current is smaller than one provided by the voltage regulator during normal mode of the memory device.
    Type: Grant
    Filed: May 17, 2012
    Date of Patent: October 22, 2013
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventor: Chung Zen Chen
  • Patent number: 8526244
    Abstract: An anti-fuse circuit including a programmable module, a read module, and a control module is provided. The programmable module has a plurality of data cells. The read module is coupled to the programmable module. During a normal operation, the read module distinguishes which one or more of the data cells are stressed. The control module is coupled to the programmable module. During a stress operation, the control module controls each stressed data cell to be coupled to a high voltage, a low voltage, and a control voltage. The first end of each stressed data cells is coupled to the low voltage, the second end of each stressed data cells is coupled to the high voltage, and the control end of each stressed data cells is coupled to the control voltage during the stress operation.
    Type: Grant
    Filed: July 21, 2011
    Date of Patent: September 3, 2013
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventor: Ming-Chien Huang
  • Patent number: 8514005
    Abstract: A circuit for generating multiphase clock signals and corresponding indication signals is provided. The circuit includes a multiphase clock generation circuit, a DLL circuit, a timing circuit, and a phase comparison circuit. The multiphase clock generation circuit receives an external clock to provide a plurality of first clock signals, phases of which differ from one another. The DLL circuit receives the external clock signal to provide a second clock signal. The timing circuit receives the second clock signal and a comparison signal to provide a plurality of indication signals. Each of the plurality of indication signals has rising edges which lead the rising edges of a corresponding one of the first clock signals. The phase comparison provides the comparison signal if a delayed phase of the corresponding one of the indication signals is within a phase of one of the first clock signals.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: August 20, 2013
    Assignee: Elite Semiconductor Memory Technology, Inc.
    Inventors: Ming-Chien Huang, Chien-Yi Chang
  • Patent number: 8498165
    Abstract: A data outputting method of a memory circuit is illustrated. The memory circuit having at least 16 data buffers DQ[0]˜DQ[15] for storing at least 16 batches of data is provided. If a quadruple data outputting mode is selected for the memory circuit, when the clock signal triggers the 16 data buffers DQ[0]˜DQ[15], the 4 batches of the data stored in the 4 data buffers DQ[0], DQ[1], DQ[8], DQ[9] via 4 input/output pins connected to the 4 data buffers DQ[0], DQ[1], DQ[8], DQ[9], the batch of data stored in the data buffer DQ[2n+2] is transferred to be stored in the data buffer DQ[2n], and the batch of the data stored in the data buffer DQ[2n+3] is transferred to be stored in the data buffer DQ[2n+1], for n is an integer from 0 through 2, and from 4 through 6.
    Type: Grant
    Filed: July 7, 2010
    Date of Patent: July 30, 2013
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventors: Tzeng-Ju Hsue, Chih-Hao Chen
  • Patent number: 8498167
    Abstract: A semiconductor memory device with a self-refresh timing circuit is provided. The semiconductor memory device comprises a plurality of memory banks, a command decoder, a bank address generator, a self-refresh counter, and the self-refresh timing circuit. The self-refresh timing circuit comprises a temperature sensor, a reference voltage source, a comparison circuit, an enable circuit, and an oscillation circuit. The comparison circuit compares a voltage from the temperature sensor with a constant voltage from the reference voltage source and generates a comparison signal. The enable circuit activates the comparison circuit when self-refresh operations for at least one refresh row are completed in all memory cell banks. The oscillation circuit generates a self-refresh clock signal which controls the operating frequency of the bank address generator and the self-refresh counter.
    Type: Grant
    Filed: January 20, 2012
    Date of Patent: July 30, 2013
    Assignee: Elite Semiconductor Memory Technology, Inc.
    Inventor: Ming-Chien Huang
  • Publication number: 20130188429
    Abstract: A semiconductor memory device with a self-refresh timing circuit is provided. The semiconductor memory device comprises a plurality of memory banks, a command decoder, a bank address generator, a self-refresh counter, and the self-refresh timing circuit. The self-refresh timing circuit comprises a temperature sensor, a reference voltage source, a comparison circuit, an enable circuit, and an oscillation circuit. The comparison circuit compares a voltage from the temperature sensor with a constant voltage from the reference voltage source and generates a comparison signal. The enable circuit activates the comparison circuit when self-refresh operations for at least one refresh row are completed in all memory cell banks. The oscillation circuit generates a self-refresh clock signal which controls the operating frequency of the bank address generator and the self-refresh counter.
    Type: Application
    Filed: January 20, 2012
    Publication date: July 25, 2013
    Applicant: Elite Semiconductor Memory Technology Inc.
    Inventor: Ming-Chien Huang
  • Patent number: 8482992
    Abstract: A method for controlling operations of a delay locked loop (DLL) of a dynamic random access memory (DRAM) is provided herein. A phase detector of the DLL compares an external clock signal with a feedback clock signal to generate a first control signal. A delay line circuit of the DLL delays the external clock signal according to the first control signal. A detector of the DRAM detects variations of the first control signal to determine a length of an enable period of an enable signal. The delay line circuit and the output buffer are active only during the enable period when the DRAM is in a standby mode.
    Type: Grant
    Filed: July 28, 2011
    Date of Patent: July 9, 2013
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventor: Ming-Chien Huang
  • Patent number: 8472265
    Abstract: A novelty repairing method and circuit are provided by the embodiments of the present invention, wherein the input/output (IO) compression manner can be used therein to reduce the access time during the chip probing 1 (CP1) test, and each redundant column selected line (RCSL) can be divided into several partial redundant column selected lines (P-RCSLs) which are respectively responsible for repairing the defects of the corresponding regions. Based upon the repairing method, the memory circuit can reduce the number of the RCSLs. Furthermore, a variable region dividing manner is applied therein, so as to increase the probability for repairing the defect of the memory circuit.
    Type: Grant
    Filed: May 10, 2011
    Date of Patent: June 25, 2013
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventor: Jen-Shou Hsu
  • Patent number: 8462571
    Abstract: A dynamic random-access memory (DRAM) and a method for testing the DRAM are provided. The DRAM includes a memory cell, a bit line associated with the memory cell, a local buffer, and a bit line sense amplifier (BLSA). The local buffer receives a first power voltage as power supply. The local buffer provides a ground voltage to the bit line when a data signal is de-asserted and provides the first power voltage to the bit line when the data signal is asserted. The BLSA receives a second power voltage as power supply. The BLSA provides the second power voltage to the bit line when the data signal and a wafer level burn-in test signal are both asserted. The second power voltage may be higher than the first power voltage. The wafer level burn-in test signal is asserted when the DRAM is in a wafer level burn-in test mode.
    Type: Grant
    Filed: July 19, 2011
    Date of Patent: June 11, 2013
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventor: Min-Chung Chou
  • Patent number: 8456211
    Abstract: A slew rate control circuit is provided. The slew rate control circuit includes at least one switch and an inverter. A first end of the switch is coupled to a power terminal. A toggle end of the switch is coupled to a first control terminal. A second end of the switch is coupled to an output terminal. An output end of the inverter is coupled to the output terminal. An input end of the inverter is coupled to an input terminal. A voltage at the first control terminal conducts the switch to reduce the slew rate when a large voltage variation occurs at the output terminal. A method of controlling a slew rate and a slew rate control device are provided.
    Type: Grant
    Filed: May 12, 2010
    Date of Patent: June 4, 2013
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventors: Chin-Yang Chen, Jian-Wen Chen
  • Publication number: 20130100734
    Abstract: A method of trimming a reference cell in a semiconductor memory device comprises the steps of: generating a reference current based on a bias voltage applied to the reference cell; generating a first current and a second current based on the value of a control voltage and the resistance of a precision resistor disposed outside the semiconductor memory device; comparing the reference current with the first current; comparing the reference current with the second current; programming the reference cell if the value of the reference current is greater than that of the first current; and erasing the reference cell if the value of the reference current is less than that of the second current. The value of the second current is less than that of the first current.
    Type: Application
    Filed: October 19, 2011
    Publication date: April 25, 2013
    Applicant: Elite Semiconductor Memory Technology, Inc.
    Inventor: Chung-Shan KUO
  • Patent number: 8427889
    Abstract: A main word line driving circuit for driving word lines in a memory device comprises first and second level shifting units and an inverting unit. The first level shifting unit is configured to convert a decode signal into a first operative signal, and the second level shifting unit is configured to convert the decode signal into a second operative signal. The inverting unit is configured to receive the first and second operative signals. A supply voltage of the first level shifting unit is selectively switched to a first bias voltage when the plurality of word lines are selected or partially selected and switched the output voltage to a second bias voltage when the plurality of word lines are deselected.
    Type: Grant
    Filed: February 26, 2010
    Date of Patent: April 23, 2013
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventor: Min Chung Chou
  • Patent number: 8405375
    Abstract: A circuit for providing a reference voltage includes a bandgap reference circuit, a first unity gain buffer coupled to the bandgap reference circuit, a first switch for coupling a second reference voltage node to a third reference voltage node, a first capacitor coupled to the third reference voltage node, a second switch for coupling the third reference voltage node to a fourth reference voltage node, and a second capacitor coupled to the fourth reference voltage node, wherein during operation a fourth reference voltage at the fourth reference voltage node decays when the second capacitor discharges. A control circuit provides control signals for intermittently operating the bandgap reference circuit and for controlling the switches to recharge the second capacitor after the fourth reference voltage decays a predetermined amount.
    Type: Grant
    Filed: June 24, 2011
    Date of Patent: March 26, 2013
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventor: Chung-Zen Chen