803results about "Power reduction in field effect transistors" patented technology

It is an object to provide a semiconductor device in which power consumption can be reduced. It is another object to provide a highly reliable semiconductor device using a programming cell, such as a programmable logic device (PLD). In accordance with a change in a configuration of connections between basic blocks, power supply voltage furnishing to the basic blocks is changed. That is, when the structure of connections between the basic blocks is such that a basic block does not contribute to a circuit, the supply of the power supply voltage to this basic block is stopped. Further, the supply of the power supply voltage to the basic blocks is controlled using a programming cell formed using a field effect transistor whose channel formation region is formed using an oxide semiconductor, the field effect transistor having extremely low off-state current or extremely low leakage current.

A method for compensating the threshold voltage roll-off using transistors containing back-gates or body nodes is provided. The method includes designing a semiconductor system or chip having a plurality of transistors with a channel length of Lnom. For the present invention, it is assumed that the channel length of these transistors at the completion of chip manufacturing is Lmax. This enables one to set the off-current to the maximum value of I-offmax which is done by setting the threshold voltage value to Vtmin. The Vtmin for these transistors is obtained during processing by using the proper implant dose. After manufacturing, the transistors are then tested to determine the off-current thereof. Some transistors within the system or chip will have an off-current value that meets a current specification. For those transistor devices, no further compensation is required. For other transistors within the system or chip, the off-current is not within the predetermined specification. For those transistors, threshold voltage roll-off has occurred since they are transistors that have a channel length that is less than nominal. For such short channel transistors, the threshold voltage is low, even lower than Vtmin, and the off-current is high, even higher than I-offmax. Compensation of the short channel transistors is achieved in the present invention by biasing the back-gate or body node to give increased threshold voltage about equal to Vtmin and hence an off-current that meets the predetermined specification, which is about equal to I-offmax.

A circuit capable of reducing a consumption current is provided for a digital display device composed of unipolar TFTs. There is provided a latch circuit for holding a digital video signal. According to the latch circuit, when the digital video signal is inputted to an input electrode of a TFT (101), a non-inverting output signal is outputted from an output electrode of the TFT (101) and an inverting output signal is outputted from output electrodes of TFTs (102 and 103). Two line outputs of non-inversion and inversion are obtained. Thus, when a buffer located in a subsequent stage is operated, a period for which a direct current path is produced between a high potential and a low potential of a power source can be shortened, thereby contributing to reduction in a consumption current.

An improved level shifter circuit that toggles a "flying Flip-Flop" comprising a cross-coupled inverter pair with control devices driven out of phase through a pair of cascode transistors. The cross-coupled inverter pair provides pull-up to the positive rail, clamping to a High Side-Common (HSC), and providing Hysteretic Switching. The cascode transistors restrict the pull-down of the control devices, thereby preventing continuous current conduction.

In a semiconductor integrated circuit, respective semiconductor circuits are disposed in different regions partitioned in accordance with their operation probabilities per unit time, and a supply voltage and a threshold voltage are correlatively controlled in each region. A target value for controlling the threshold voltage is determined in accordance with the operation probability of the semiconductor circuit. A threshold voltage control circuit controls substrate voltages of p-type and n-type MOS transistors included in the semiconductor circuit so that the threshold voltage can be constant at the target value regardless of the temperature change occurring in use. Simultaneously, a supply voltage control circuit controls the supply voltage for the semiconductor circuit so that an objective operating frequency can be attained. As a result, a semiconductor integrated circuit with low power consumption can be obtained.

A compact level shifter is provided, which has a low consumption power and speedy operation, capable of easily performing a level conversion of voltage levels having a large difference. A voltage regulating circuit (10a), a P channel MOS electric field effect transistor (hereinafter referred to as PMOST), a PMOST (103), and an N channel MOS electric field effect transistor (hereinafter referred to as NMOST) (105) are connected in series between 2 power sources. Similarly, a voltage regulating circuit (10b), a PMOST (102), a PMOST (104), and an NMOST (106) are connected in series between 2 power sources. During the flow of a penetrating current in a transient period of a level conversion operation, a power source voltage is effectively reduced by the above-mentioned voltage regulating circuit, whereby the level conversion of the voltage level having a large difference is made easy.

Disclosed is a programmable logic device (PLD) which can undergo dynamic configuration at a high speed. The PLD includes a plurality of programmable logic elements (PLEs) and a switch for selecting electrical connection between the PLEs. The switch includes a plurality of circuit groups each of which includes first and second transistors. The second transistors of the circuit groups are electrically connected in parallel with one another. In each of the circuit groups, the electrical conduction between a source and a drain of the second transistor is determined based on configuration data held at a node between the gate of the second transistor and a drain of the first transistor, which allows the selection of the electrical connection and disconnection between the programmable logic elements by the selection of one of the circuit groups.

Disclosed is a semiconductor integrated circuit device constructed of MOSFETs in which there is attained a harmony between increase in consumption power due to a leakage current and operating speed of the MOSFETs in a suitable manner, and among a plurality of signal paths in the semiconductor integrated circuit device, a path which has a margin in delay is constructed with MOSFETs each with a high threshold voltage, while a path which has no margin in delay is constructed with MOSFETs each with a low threshold voltage which has a large leakage current but a high operating speed, in light of a delay with which a signal is transmitted along a signal path.

An object is to provide a programmable logic device having logic blocks connected to each other by a programmable switch, where the programmable switch is characterized by an oxide semiconductor transistor incorporated therein. The extremely low off-state current of the oxide semiconductor transistor provides a function as a non-volatile memory due to its high ability to hold a potential of a gate electrode of a transistor which is connected to the oxide semiconductor transistor. The ability of the oxide semiconductor transistor to function as a non-volatile memory allows the configuration data for controlling the connection of the logic blocks to be maintained even in the absence of a power supply potential. Hence, the rewriting process of the configuration data at starting of the device can be omitted, which contributes to the reduction in power consumption of the device.

An object is to achieve both suppression of operation delay and reduction in power consumption of a programmable LSI. A compiler generates, from source code, configuration data needed in a programmable LSI and a time schedule that shows a timing of using the data in the programmable LSI (a timing at which the data is held in a configuration memory) and a timing of storing the data in the programmable LSI before the data is used. Supply of new configuration data to the programmable LSI from the outside (storage of new configuration data) and data rewrite in the configuration memory in the programmable LSI (circuit reconfiguration) are performed independently and concurrently on the basis of the time schedule.

An adaptive supply voltage and body bias apparatus includes a master controller including an operation state value. The apparatus and method includes a dynamic voltage supplier coupled to the master controller operative to receive a supply voltage indicator. The apparatus and method includes an adaptive body biaser coupled to the master controller operative to receive a body bias indicator. Furthermore, the apparatus and method includes a plurality of computing devices each having one of a plurality of threshold voltages. The plurality of computing devices are operative to receive the supply voltage from the dynamic voltage supplier and a bias voltage from the adaptive body biaser for optimized power supply in conjunction with reduction of power leakage in view of the varying threshold voltage of the computing devices.

A clock architecture for a Structured ASIC chip, manufactured using a CMOS process is shown. A via-configurable logic block (VCLB) architecture in the Structured ASIC has a core region containing memory and logic cells arranged in columns that are supplied by a clock network having a global clock network tree and a low-level clock mesh to distribute the global clock signal in a repeating pattern. The clock mesh has a fishbone configuration in outline and allows for scalable expansion of the clock network. In one embodiment 36 global clocks may be provided to the Structured ASIC, with four clocks per logic cell. The VCLB Structured ASIC chip is manufactured on a 28 nm CMOS process lithographic node, having several metal layers but preferably is programmable on a single via layer.

A switched bridge circuit comprises a first switch, a second switch, and a non-overlapping pulse generator. The first switch is coupled to a load. The second switch is coupled to said load. The non-overlapping pulse generator is coupled to the first switch and the second switch and coupled to receive an input signal. The non-overlapping pulse generator in response to the input signal generates a first control signal and a second control signal that respectively control the first and second switches. The pulses in the first and second control signals are not overlapped so that the first and second switches are not simultaneously enabled.

Disclosed are keeper circuits for electronic circuits that selectively maintain the voltage level of an intermediate circuit node at a desired level. In one exemplary embodiment, a keeper transistor either provides current or drains current from the intermediate node to maintain the desired voltage level in response to a signal to do so. The keeper circuit works against a leakage current that either drains current from the node or supplies current to the node. A current-setting transistor is coupled in series with the keeper transistor to set the maximum current through the keeper circuit to a value that is related to this leakage current, preferably tracking the leakage current. With this construction, the current-setting transistor is able to track variations in the leakage current caused by variations in the manufacturing process, and thereby provide dynamic leakage compensation.

A domino logic circuit is configured to reduce power consumption. In a first embodiment, a sleep switch grounds the dynamic node during sleep mode. In a second embodiment, a low-swing circuit at the output reduces the output and keeper transistor gate voltage swings. A third embodiment combines those two techniques.

A method for driving a semiconductor device capable of reducing an area of a multiplexer and reducing its power consumption is provided. In a method for operating a semiconductor device including a memory and a multiplexer, a first transistor is connected to a first capacitor, and a second transistor is connected to a second capacitor. In the multiplexer, in a third transistor, a source is connected to a first input terminal and a drain is connected to an output terminal and, in a fourth transistor, a source is connected to a second input terminal and a drain is connected to the output terminal. Further, a step of holding a first potential in a node to which the first transistor, the first capacitor, and a gate of the third transistor are connected and holding a second potential higher than the first potential in the node is included.

Data of a register in a programmable logic element is retained. A volatile storage circuit and a nonvolatile storage circuit are provided in a register of a programmable logic element whose function can be changed in response to a plurality of context signals. The nonvolatile storage circuit includes nonvolatile storage portions for storing data in the register. The number of nonvolatile storage portions corresponds to the number of context signals. With such a structure, the function can be changed each time context signals are switched and data in the register that is changed when the function is changed can be backed up to the nonvolatile storage portion in each function. In addition, the function can be changed each time context signals are switched and the data in the register that is backed up when the function is changed can be recovered to the volatile storage circuit.

A circuit for use in conjunction with a portion of a core of an integrated circuit, for shifting a signal from a first voltage level to a second voltage level, wherein the circuit is formed using the same process type transistors (i.e., low voltage transistors) as are used in the core of the integrated circuit.

A level shifter may reduce leakage current and provide firewall protection between circuits of different voltage domains when one voltage domain is in a standby mode. The level shifter may either couple or decouple input circuitry from a reference voltage in response to a firewall enable signal, may translate signals between a first voltage domain and a second voltage domain when the firewall enable signal is deasserted, and may generate an output signal having a predetermined one of either a high or low state when the firewall enable signal is asserted.

A programmable analog device and an analog device that can retain data even when supply of a power supply potential is interrupted and consumes less power. In a semiconductor device, first to fourth transistors are used as switches in a unit cell including an analog element, and the output of the unit cell switches between a conducting state, a non-conducting state, and a conducting state through the analog element by controlling the potential of a first node where the first transistor and the second transistor are connected and the potential of a second node where the third transistor and the fourth transistor are connected.

As semiconductor devices including semiconductors, logic circuits are given. Logic circuits include dynamic logic circuits and static logic circuits and are formed using transistors and the like. Dynamic logic circuits can store data for a certain period of time. Thus, leakage current from transistors causes more severe problems in dynamic logic circuits than in static logic circuits. A logic circuit includes a first transistor whose off-state current is small and a second transistor whose gate is electrically connected to the first transistor. Electric charge is supplied to a node of the gate of the second transistor through the first transistor. Electric charge is supplied to the node through a first capacitor and a second capacitor. On / off of the second transistor is controlled depending on a state of the electric charge. The first transistor includes an oxide semiconductor in a channel formation region.

Disclosed are keeper circuits for electronic circuits that selectively maintain the voltage level of an intermediate circuit node at a desired level. In one exemplary embodiment, a keeper transistor either provides current or drains current from the intermediate node to maintain the desired voltage level in response to a signal to do so. The keeper circuit works against a leakage current that either drains current from the node or supplies current to the node. A current-setting transistor is coupled in series with the keeper transistor to set the maximum current through the keeper circuit to a value that is related to this leakage current, preferably tracking the leakage current. With this construction, the current-setting transistor is able to track variations in the leakage current caused by variations in the manufacturing process, and thereby provide dynamic leakage compensation.

A flip-flop circuit having low power consumption includes a sensing circuit, and a clock generating circuit. The flip-flop is leading edge triggered and operates on an internally generated pseudo clock signal. The sensing circuit senses a change in an input signal and an output signal of the flip-flop. The clock generating circuit generates a pseudo clock signal with a sharp rise and fall based upon an external clock signal.

The present invention provides power saving methods by replacing termination resistors used to support SSTL DRAM interfaces with RC termination circuits; the RC termination circuits consumes significant less power relative to prior art termination resistors at low frequency and behave as a matching impedance at high frequency. Similar methods and structures are also applicable for PCIe, SATA, or MIPI differential interfaces.

A buffer circuit includes first to sixth transistors. The first transistor is coupled between a first power source and a first node, and has a gate for receiving a first signal having a first signal level. The second transistor is coupled between the first node and a second power source, and has a gate for receiving a second signal having a second signal level, which is an inverse of the first signal level. The third transistor has a gate coupled to the first node, and is coupled between the first power source and a second node. The fourth transistor is coupled between the second node and the second power source, and has a gate for receiving the first signal. The fifth transistor has a gate coupled to the second node, and is coupled between the first power source and an output end. The sixth transistor has a gate coupled to the first node, and is coupled between the output end and the second power source. In addition, a capacitance is formed between the gate of the sixth transistor and the output end.

A range sensor and a method thereof. The range sensor includes a light source configured to project a sheet of light at an angle within a field of view (FOV); an image sensor offset from the light source; collection optics; and a controller connected to the light source, the image sensor, and the collection optics, and configured to determine a range of a distant object based on direct time-of-flight and determine a range of a near object based on triangulation. The method includes projecting, by a light source, a sheet of light at an angle within an FOV; offsetting an image sensor from the light source; collecting, by collection optics, the sheet of light reflected off objects; and determining, by a controller connected to the light source, the image sensor, and the collection optics, a range of a distant object based on direct time-of-flight and a range of a near object based on triangulation simultaneously.