37results about How to "Increase voltage margin" patented technology

A memory uses multiple threshold levels in a memory cell that are not a power of two, and further uses a cell mapping technique wherein the read mapping is only a partial function The domain of read states for a single three-level memory cell, for example, has three states, but only two of them can be uniquely mapped to a bit. The domain of read states for two three-level memory cell, for example, has nine states, but only eight of them can be uniquely mapped to three bits. Although the read mapping is only partial, the voltage margin for the three-level memory cells is larger that the voltage margin available in the commonly used four-level memory cells. This increased voltage margin facilitates memory cell threshold voltage sensing, thereby increasing the reliability of the memory. Memory reliability may be further improved by increasing the voltage margin between the memory cell 0 state and the 1 state relative to the voltage margin between the 1 state and the 2 state, which more effectively accommodates charge loss from the 0 state through electron leakage. Asymmetrical read and program mapping may also be used to improve read reliability in the presence of ground noise or VCC noise.

A non-volatile ferroelectric memory device senses a cell data at high speed. Preferably, the non-volatile ferroelectric memory device includes a plurality of cell array blocks, a plurality of sense amplifier units, a plurality of sense amplifier units, a plurality of local data buses, a global data bus, and a plurality of data bus switch arrays. Each of the plurality of cell array blocks has a hierarchical bit line architecture including sub bit lines and a main bit line group corresponding to a plurality of unit cells for storing differential data. The plurality of sense amplifier units, corresponding one-by-one to the cell array blocks, sense and amplify the differential data induced on the main bit line group during a sensing operation. The plurality of local data buses, corresponding one-by-one to the sense amplifier units, transfer the differential data outputted from the sense amplifier units and differential data to be transferred to the sense amplifier units. The global data bus, shared by a plurality of the local data buses, transfers the differential data. The plurality of data bus switch arrays selectively couple the local data buses to the global data bus.

A storage node voltage control circuit is added to a memory cell including two load transistors, two drive transistors and two access transistors. The storage node voltage control circuit performs control so that in writing data into the memory cell, a voltage at one of the two storage nodes holding a low logic level is raised without changing voltages at respective sources of the load transistors.

According to a plasma display apparatus of the present invention, at least in one sub-field, a driving signal applied to retain data written in each pixel has a frequency applied first and a frequency applied thereafter, the frequencies being different from each other. The first frequency is controlled to be low and the frequency thereafter is controlled to be high, for example (two-frequency driving method). With a first low-frequency pulse, initial discharge in a sustaining period is started stably, and with a high-frequency pulse thereafter, the discharge is sustained. Use of the high-frequency pulse increases the number of light emissions, thus leading to improvement in brightness. Thus, the present invention enables both discharge stabilization and increase in brightness, and can therefore improve picture quality of the plasma display apparatus.

According to a plasma display apparatus of the present invention, at least in one sub-field, a driving signal applied to retain data written in each pixel has a frequency applied first and a frequency applied thereafter, the frequencies being different from each other. The first frequency is controlled to be low and the frequency thereafter is controlled to be high, for example (two-frequency driving method). With a first low-frequency pulse, initial discharge in a sustaining period is started stably, and with a high-frequency pulse thereafter, the discharge is sustained. Use of the high-frequency pulse increases the number of light emissions, thus leading to improvement in brightness. Thus, the present invention enables both discharge stabilization and increase in brightness, and can therefore improve picture quality of the plasma display apparatus.

An organic light emitting display, and a method of driving the same, controls the voltage of a second power source in accordance with an ambient temperature. The organic light emitting display includes a driver IC configured to drive a pixel unit and to generate a control signal in accordance with an ambient temperature, and a DC-DC converter configured to generate a first power source and a second power source from an input voltage, to change a voltage of the second power source in accordance with the control signal from the driver IC, and to output the changed voltage of the second power source and the first power source.

A non-volatile semiconductor memory having a memory transistor including a stacked-layer film formed between a semiconductor substrate and a gate electrode and having a charge storage ability, a first conductivity type region of the semiconductor substrate in which a channel is formed under the control of the gate electrode via the stacked-layer film, and two second conductivity type regions formed at the semiconductor substrate sandwiching the first conductivity type region therebetween, the memory transistor having a channel length L which is between channel lengths L1 and L2. with the channel length L1 being estimated as the boundary of occurrence of a short channel effect at the time of a write operation and the channel length L2 the time of a read operation, with the channel length L1 being different from the channel length L2.

The invention discloses a method for improving the scanning pulse voltage and reducing power consumption. By improving the scanning pulse voltage and adjusting the step voltage of the scanning driving voltage, the purpose of increasing voltage margin and reducing power consumption is finally achieved. Each subfield is divided into an initialization period, an address period, and a sustain period. The formation circuit during the initialization period is composed of the formation circuit b of the rising edge of the ramp and the formation circuit c of the falling edge of the ramp; the formation circuit during the addressing period is composed of a step voltage The formation circuit d of Yp, the formation circuit g of negative pressure-Vy and the scanning chip e are formed; the formation circuit during the maintenance period is composed of the energy recovery circuit a; the invention can increase the voltage margin, reduce power consumption, and improve image quality.

According to a plasma display apparatus of the present invention, at least in one sub-field, a driving signal applied to retain data written in each pixel has a frequency applied first and a frequency applied thereafter, the frequencies being different from each other. The first frequency is controlled to be low and the frequency thereafter is controlled to be high, for example (two-frequency driving method). With a first low-frequency pulse, initial discharge in a sustaining period is started stably, and with a high-frequency pulse thereafter, the discharge is sustained. Use of the high-frequency pulse increases the number of light emissions, thus leading to improvement in brightness. Thus, the present invention enables both discharge stabilization and increase in brightness, and can therefore improve picture quality of the plasma display apparatus.

A semiconductor memory device includes memory modules which have memories and a data bus which transfers data to the memory modules, in which the data bus comprises a low frequency band data pass unit which removes the high frequency component of the data and sends the data to the memory modules. The low frequency band data pass unit comprises a plurality of stubs which are connected to the data bus in parallel and are formed as printed circuit board (PCB) patterns. The low frequency band data pass unit comprises a plurality of plates that are connected to the data bus in parallel and are formed as PCB patterns. The low frequency band data pass unit has a shape in which parts having a wide width and parts having a narrow width are alternately connected. Therefore, without adding a separate passive device, the semiconductor memory device reduces the high frequency noise of data transferred through a data bus such that the voltage margin of the data improves, the cost for passive devices such as capacitors, is reduced, and the process for attaching the passive devices is simplified.

A phase change memory device having an improved performance that minimizes cell degradation is presented. The phase change memory device includes: a cell array, a sense amplifier, a write driving unit, and a reference level selecting unit. The cell array has a phase change resistor is configured to read / write data. The sense amplifier is configured to compare a reference voltage with a sensing voltage received from the cell array. The write driving unit is configured to supply a driving voltage corresponding to write data to the cell array. The reference level selecting unit is configured to select a read reference voltage in a read mode so as to output the reference voltage, and to select a reference voltage corresponding to input data in a write verifying mode so as to output the reference voltage.

The invention discloses a field weakening control method for a built-in permanent magnet synchronous motor based on a torque feedforward control technology, which mainly comprises a stator flux adjustment module, a current data table, a current regulator, a pulse width modulation module, dq-[alpha][beta] transformation, Park transformation, an uncontrolled rectifier bridge and an inverter, and ischaracterized in that the stator flux adjustment module calculates an appropriate stator flux set value to serve as the output according to an input torque set value, DC bus voltage, motor speed and amodulation factor; the stator flux adjustment module comprises seven modules I-VII, wherein the module I is a one-dimensional table and records the corresponding minimum stator flux at different given torques. The field weakening control method realizes the maximization of torque output of the motor in a field weakening area through introducing a proportionality factor into stator flux adjustment, and ensures the stability of the torque at the same time. The factor automatically changes in size according to operating conditions of the current motor, the voltage margin is improved when the speed is high and the torque is low, the torque output capacity is improved when the speed is high and the torque is large, and thus the maximum utilization ratio of the DC bus voltage is achieved.

The present invention provides a transconductance amplifier comprising an input circuit, a gain circuit and an output circuit which are successively connected. The gain circuit comprises a MOS transistor array composed of a plurality of MOS transistors, grids of the corresponding MOS transistors between every two adjacent columns of the MOS transistor array are connected, the MOS transistors in each column of the MOS transistors are successively connected, and compensation capacitors are arranged between asymmetrical connection points of the MOS transistors in the output column of the MOS transistor array and an output terminal of the output circuit. According to the transconductance amplifier, compared with a traditional frequency compensation technology, dominant pole frequency of the transconductance amplifier can be reduced through increasing capacitance values of the compensation capacitors, right half plane zero frequency of the transconductance amplifier can also be prevented from being reduced, so that a distance between the dominant pole frequency and the right half plane zero frequency of the transconductance amplifier can be increased, the influence of frequency compensation on frequency characteristics of the transconductance amplifier can be reduced, unity-gain bandwidth of the transconductance amplifier can be improved, and the problem that the transconductance amplifier is possibly unstable can be solved.