103results about "Threshold modification in field effect transistors" patented technology

The present invention is directed to realize high manufacture yield and compensate variations in threshold voltage of a MOS transistor with small overhead. A semiconductor integrated circuit includes a CMOS circuit for processing an input signal in an active mode, a control switch, and a control memory. The control switch supplies a pMOS body bias voltage and an nMOS body bias voltage to an N well in a pMOS transistor and a P well in an nMOS transistor, respectively, in the CMOS circuit. The control memory stores control information indicating whether or not the pMOS body bias voltage and the nMOS body bias voltage are supplied from the control switch to the N well in the pMOS transistor and the P well in the nMOS transistor, respectively, in the CMOS circuit in the active mode.

The basic cell constituted by a semiconductor integrated circuit comprises two PMOS transistors and two NMOS transistors. By setting the gate widths of the gates of these transistors to prescribed lengths, the efficiency of use of elements within the basic cell is improved, and fine adjustment of the threshold voltage Vth and delay time Tpd becomes possible.

Power dissipation of a semiconductor integrated circuit chip is reduced when it is operated at an operating voltage of 2.5 V or below. A switching element is provided in each circuit block within the chip. Constants of the switching element are set so that leakage current in each switching element in their off-state is smaller than the subthreshold current of MOS transistors within the corresponding circuit block. Active current is supplied to active circuit blocks, while switching elements of non-active circuit blocks are turned off. Thus, dissipation currents of non-active circuit blocks are limited to leakage current value of corresponding switching elements. Thus, the sum of dissipation currents of non-active circuit blocks is made smaller than the active current in the active circuit blocks. As a result, power dissipation in the semiconductor integrated circuit chip can be reduced even in the active state.

A well-bias system dynamically adjusts well-bias set points to optimal levels across an integrated circuit (IC) for enhanced power savings and component reliability during a standby or low-power mode of operation. A controller within the IC determines if the chip power supply voltage will be reduced during an imminent standby or low power mode and sets a register controlling a negative well-bias set point for asserting well-bias to charge wells of the IC accordingly. To minimize leakage current without compromising reliability, the well-bias set point is set to (1) an optimal well-bias set point if a reduced supply voltage is to be applied to the IC, or (2) a minimum well-bias set point when a nominal or high supply voltage is to be applied to the IC.

Apparatus and methods may operate so that arrival times of a data signal at gates of transistors are controlled to switch the transistors at different times to modulate the slew rate of a signal on a node. Additional embodiments are also described.

Methods, systems, computer readable media and means for reducing errors in data caused by noise are provided. In some embodiments of the present invention, timing data is transferred from first circuitry to second circuitry. From the timing data, one or both of the first circuitry and the second circuitry detect whether noise is present as a result of the operations of the first circuitry. If it is detected that noise is present the second circuitry waits for the cessation of the noise before functioning again. If it is detected that no noise is present, the second circuitry functions.

It is described a circuit and a method for transforming an input signal into a logical output. The circuit (100) comprises an inverter stage (120), connected in between the first conductor (101) and the second conductor (102). The inverter stage (120) includes a MOS switch (MP0), which comprises a first terminal being connected to the first conductor (101), a second terminal being connected to an output node (hyst), a gate terminal being connected to an input node (JN), and a back gate terminal. The circuit (100) further comprises a voltage divider (130), connected in between the first conductor (101) and the output node (hyst), wherein the voltage divider (130) provides a divider output node (bg) being connected to the back gate terminal. The circuit (100) represents an input cell having an improved hysteresis behavior over the total operating voltage range. This is achieved by adjusting the back gate voltage of the MOS switch (MP0) during a transition from an input level Low to an input level High. This causes a temporarily increased threshold voltage for turning off the MOS switch (MP0) during the transition.

A level shifter, with body-biased circuits, is provided for applying in a thin film transistor liquid crystal display (TFT-LCD). The body-biased circuits are configured to bias the bodies of the input terminal transistors of the level shifter so that the threshold voltages of the input terminal transistors are adjustable. This level shifter is capable of operating at a high frequency with low power consumption while a low-level signal is inputting.

A semiconductor device with a small number of transistors is provided. The semiconductor device includes a first transistor, a second transistor, a third transistor, a first wiring, and a second wiring. The first transistor includes a first gate and a second gate. The first gate and the second gate overlap with each other with a semiconductor therebetween. The first wiring and the second wiring are supplied with a high power supply potential and a low power supply potential, respectively. A first terminal of the first transistor is electrically connected to the first gate and the first wiring. A second terminal of the first transistor is electrically connected to the second gate. The second terminal of the first transistor is electrically connected to the second wiring through the second transistor and the third transistor. The first transistor, the second transistor, and the third transistor are preferably n-channel transistors.

In one embodiment, an integrated circuit comprises a first circuit and a control unit coupled to the first circuit. The first circuit comprises at least one transistor and implements one or more operations for which the integrated circuit is designed. The control unit is configured to generate at least one substrate bias voltage for the first circuit.

Impedance-matched output driver circuits utilize predriver circuits with analog control to provide enhanced operating characteristics. This analog control may be provided by an analog loop containing differential amplifiers that set the resolution limit of the output driver circuit. These output driver circuits include a first PMOS pull-up transistor having source and drain terminals electrically connected in series in a pull-up path of the output driver circuit. An NMOS pass transistor has a first current carrying terminal electrically connected to a gate terminal of the first PMOS pull-up transistor and a second current carrying terminal configured to receive a P-type analog reference voltage (VP). This P-type reference voltage controls the conductivity of the first PMOS pull-up transistor in the pull-up path. A gate terminal of the NMOS pass transistor is responsive to a pull-up data input signal (DINP). A first NMOS pull-down transistor has source and drain terminals that are electrically connected in series in a pull-down path of the output driver circuit. A PMOS pass transistor is provided having a first current carrying terminal electrically connected to a gate terminal of the first NMOS pull-down transistor and a second current carrying terminal configured to receive an N-type analog reference voltage (VN). This N-type reference voltage controls the conductivity of the first NMOS pull-down transistor in the pull-down path. A gate terminal of the PMOS pass transistor is responsive to a pull-down data input signal (DINN).

A buffer circuit for providing dynamic threshold control. The buffer circuit includes a pair of input inverters designed with different skewed threshold potential characteristics. The outputs of the skewed inverters are directed to a logic circuit designed to select either the faster or the slower signal received from the two inverters for transmission to passgate devices coupled to the respective inverters. Only one of the passgate devices is enabled to ensure that only one of the output signals from the two inverters is propagated through the buffer. A latch is preferably connected between the logic circuit and the two passgate devices to maintain the states of the inverters and the logic circuit. The circuit can be designed to define the threshold potential at which switching will occur so as to reduce propagation delay or increase it as desired. It is therefore possible using the circuit to increase transmission rates with minimal affect on signal noise.

Forward bulk biasing circuitry for PMOS and NMOS transistors is provided. The bulk biasing circuitry includes two N-type MOS transistors, two P-type MOS transistors, and two capacitors. The forward bias to a bulk terminal of a transistor increases a threshold voltage of a transistor, thereby reducing a transition time and improving the performance of the transistor. The forward bias is provided only when the transistor transitions from one state to another, thereby reducing leakage power dissipation during active and standby modes of an integrated circuit that includes the transistor.

The present invention relates to a semiconductor circuit device including a logic circuit and a signal line driving circuit. The logic circuit is operated at high supply voltage and outputs a signal with a high voltage amplitude. The signal line driving circuit receives a lower supply voltage and has a low-threshold transistor. With the above configuration, a signal can be transmitted at a high speed with a low voltage amplitude and low power consumption. Thus, the semiconductor circuit device including the signal line driving circuit can reduce operating current and can be operated with a low amplitude and low standby current at a high speed.

A circuit and method for calibrating CMOS (complementary metal-oxide semiconductor) inverters are provided. In a circuit, a first tunable CMOS inverter, controlled by a control signal, receives a first voltage from a first circuit node and outputs a second voltage to a second circuit node. A second tunable CMOS inverter, controlled by the control signal, receives the second voltage from the second circuit node and outputs the first voltage to the first circuit node. A resistor couples the first circuit node to the second circuit node. A switch, controlled by a reset signal, conditionally shorts the first circuit node to the second circuit node. A finite state machine receives the first voltage and the second voltage and outputs the reset signal and the control signal, wherein the control signal is adjusted based on a difference between the first voltage and the second voltage.

An output driving device capable of improving a slew rate is provided. The output driving device includes a push-pull type driving unit configured with a pull-up PMOS transistor and a pull-down NMOS transistor, wherein body biases of the pull-up PMOS transistor and the pull-down NMOS transistor are controlled for control of a slew rate of an output signal of the driving unit.

An input buffer for interfacing a high voltage signal received at an input node to a low voltage circuit comprising low voltage devices is provided. The buffer includes a threshold adjustment circuit including an inverter coupled to a threshold adjusted output node. The inverter includes low voltage devices and is coupled between a high supply voltage node and a ground node. The inverter includes a first and second transistors having biasing nodes coupled to a low voltage supply node of the low voltage circuit and coupled to the threshold adjusted output node. The adjustment circuit provides at the threshold adjusted output node an inverted signal corresponding to the high voltage input signal. The buffer also includes a level shifting circuit including low voltage devices and provides a low voltage signal corresponding to the high voltage input signal in response to said inverted signal.