2206 results about "Reference circuit" patented technology

A double-gated low power active clamp circuit for digital circuits includes a first double-gated MOSFET serially connected between an upper power supply voltage and an input terminal to be clamped, and a second double-gated MOSFET serially connected between a lower voltage power supply and the input terminal. The voltages at the gates of the first and second double-gated MOSFETs are held at constant reference voltages by a single or double reference circuits. The clamping action can be switched on or off. The double-gated active clamping network can be implemented with a single power supply voltage, or with multiple power supply voltages. The use of the back gates of the double-gated active clamping network enables additional clamping and ESD protection for smaller generations of transistors, such as, those having dimensions below 0.1 micron. The device is particularly suited for use with dynamic threshold double-gated silicon-on-insulator, FINFET, and bulk triple well technologies.

A switching voltage regulator is disclosed for regulating a voltage supplied to system circuitry. The switching voltage regulator comprises an oscillator operable to generate an oscillator signal representing a gate speed of a reference circuit in the system circuitry, and a frequency generator operable to generate a reference signal representing a target gate speed of the reference circuit. A cycle comparator compares at least one cycle of the oscillator signal to at least one cycle of the reference signal, and switching circuitry charges a charging element based at least on part on the comparison.

The invention provides a multi-sensor integrated synchronous control method and a multi-sensor integrated synchronous control system for high-precision time-space data acquisition. The method comprises the following steps of: establishing a time-space reference circuit which provides time reference and space reference; establishing a linear reference coordinate system through the time reference and the space reference, and implementing conversion between the linear reference coordinate system and a geodetic coordinate system; sending an analog control signal to an active synchronous sensor according to the preset parameters to realize synchronous control of the active synchronous sensor; and receiving an external event pulse signal, and responding to the interruption generated by the external event pulse signal to realize synchronous control of a passive synchronous sensor. An active synchronous control circuit and a passive synchronous control circuit are provided; and based on the time and space references provided by the time-space reference circuit, the circuits can expand random multiple sensor synchronous control cases aiming at different sensors and control requirements, and have extremely strong expansion and flexible functions.

A tunable filter has a plurality of variable capacitors and a plurality of inductor elements, each being formed on a common substrate, a filter circuit formed by using at least a portion of the plurality of variable capacitors and a portion of the plurality of inductor elements, a monitor circuit formed by using at least a portion of the plurality of variable capacitors and a portion of the plurality of inductor elements, a detecting circuit which detects a prescribed circuit constant of the monitor circuit, a storage which stores information relating to a reference circuit constant of the monitor circuit, and a capacitance control circuit which controls capacitance of the variable capacitors in the monitor circuit and capacitance of the variable capacitors in the filter circuit, based on a result detected by the detecting circuit and information stored in the storage.

Systems and methods are discussed for using a floating-gate MOSFET as a programmable reference circuit. One example of the programmable reference circuit is a programmable voltage reference source, while a second example of a programmable reference circuit is a programmable reference current source. The programmable voltage reference source and/or the reference current source may be incorporated into several types of circuits, such as comparator circuits, current-mirror circuits, and converter circuits. Comparator circuits and current-mirror circuits are often incorporated into circuits such as converter circuits. Converter circuits include analog-to-digital converters and digital-to-analog converters.

A low supply voltage band-gap reference circuit is provided, which includes a positive temperature coefficient current generation unit and a negative temperature coefficient current generation unit, and it is implemented by way of current summing. Through the current-mode temperature compensation technique, the present invention is able to reduce the voltage headroom and the number of operational amplifiers required by the conventional voltage-summing method, as well as the influence to the output voltage due to the offset voltage, thereby providing a stable and low voltage band-gap reference voltage level. In addition, by reducing the number of operational amplifiers and resistors of high resistance, the circuit area is reduced, and chip cost is saved.

The present invention is an apparatus for driving white LEDs. The apparatus includes a switchable current sink, a DC-DC converter and a reference circuit. The DC-DC converter provides a driving voltage to a plurality of LEDs. The switchable current sink regulates currents through the plurality of LEDs, and the switchable current sink further provides a first reference voltage and outputs a plurality of voltage drops. The reference circuit receives the first reference voltage and the plurality of voltage drops to provide a second reference voltage to the DC-DC converter. The DC-DC converter adjusts the driving voltage provided to the plurality of LEDs according to the second reference voltage. In this way, the driving voltage is regulated to a minimum possible value and consequently the voltage drops across the switchable current sink is minimized. Hence, the LED driving system maintains higher efficiency.

A sensor for detecting a substance in liquid includes a sensing circuit including a sensing surface acoustic wave (SAW) element in which a reaction film to react with a substance in liquid, a reference circuit including a reference SAW element including an IDT and not including a reaction film, a first signal source driving the sensing circuit, a second signal source driving the reference circuit and being independent of the first signal source, and a differential circuit arranged to output a differential output between an output of the sensing circuit and an output of the reference circuit. The frequency of a first frequency signal output from the first signal source is different from the frequency of a second frequency signal output from the second signal source, thereby making a driving frequency for the sensing SAW element and a driving frequency for the reference SAW element substantially the same as or different from one another.

The invented voltage regulator is a solid state low voltage regulator for quartz halogen or low voltage incandescent lamps and quartz halogen or low voltage incandescent lamp or LED array circuits wherein the volt regulator reduces a conventional mains power line source of, for example, a 115 volt AC to 480 V AC power source, to within a range of from 11.0 volts to 12.5 volts, preferably 11.6 volts, wherein the lamps, and LED arrays have consistent color, consistent light output, the lamp filaments and LED arrays are exposed to soft start operating currents and lamp and array life can be increased. The voltage regulator utilizes an AC rectifier circuit to provide a pulsing DC voltage, a DC voltage sensing circuit, a soft start oscillator circuit, an internal DC voltage oscillator reference circuit and an AC power line control circuit.

A bandgap reference circuit includes a current generation circuit connected to a voltage generation circuit connected to a smart clamping circuit, and a discharge circuit connected to the current generation circuit and the voltage generation circuit. The discharge circuit initially discharges a potential in the current and voltage generation circuits to improve repeatability. A start circuit within the current generation circuit then initializes the reference output at about the supply voltage to improve the speed and settling time of the output signal. The current generation circuit sources a current to the voltage generation circuit that translates the current having a positive function of temperature +T_C into a reference voltage. The smart clamping circuit further generates a clamping voltage having a negative function of temperature −T_C and a load resistance. The clamping voltage and the load resistance are applied across the reference voltage quickly reducing the reference voltage particularly at high temperatures and during start-up to a final level, thereby producing a fast and stable reference voltage.

The present invention provides an improved column readout circuitry and method of operation which minimizes substrate and other common mode noise during a read out operation. The circuit improves the consistency of the pixel to pixel output of the pixel array and increases the dynamic range of the pixel output. This is accomplished by obtaining a differential readout of the reset signal and integrated charge signal from a desired pixel along with the reset signal and charge signal from a reference circuit. In this manner common mode noise can be minimized by a combination of signals from the desired and reference pixels in the sample and hold aspect of the column circuitry. In one exemplary embodiment of the invention, a 3T pixel arrangement is used. In another exemplary embodiment, a 4T arrangement is used. Additional exemplary embodiments provide differential column readout circuitry that can be used with any two signal sources.

A controller for a power converter and method of operating the same. In one embodiment, the controller includes a peak detector, coupled to a circuit element of the power converter, configured to produce a signal corresponding to a peak current through a circuit element. The controller also includes an adjustable reference circuit responsive to a difference between the signal and a reference signal corresponding to a desired peak current to produce a corrected signal corresponding to the peak current.

The invention discloses a low temperature coefficient complementary metal oxide semiconductor (CMOS) band-gap reference circuit of an output belt low drop-out linear voltage regulator. The band-gap reference circuit comprises a start-up circuit module, a band-gap reference module, a clamping operational amplifier and an output driving module based on low drop-out (LDO), wherein an output end of the start-up circuit module is connected with an input end of the band-gap reference module; an output end of the band-gap reference module is connected with an input end of the output driving module; and an output end of the output driving module is used for outputting needed band-gap reference voltage. The low drop-out linear voltage regulator is taken as an output buffer stage by the band-gap reference circuit, so that the requirement of high driving capability is met, and lower voltage output can be obtained.

The invention relates to the circuit protection field, which provides a voltage stabilizing circuit preventing overshoot and a reference circuit for solving the overshoot problem of a voltage stabilizing circuit in the prior art. The voltage stabilizing circuit preventing overshoot comprises a differential amplifier, an output stage, a control signal unit and a switch circuit. When the voltage stabilizing circuit is just powered on, the switch circuit controls the output stage according to control signals in order to restrain the output end overshoot of the output stage.

A circuit includes a first source for providing an alternating electric field, a directional circuit connected to the first source for providing an alternating electric field by a transmission conductor there being no conductive return path provided back from the directional circuit to the first source for providing an alternating electric field. The directional circuit being a loop circuit which includes one or more circuit elements causing the loop circuit to be asymmetric to current flow; the directional circuit having no continuous connective path to earth ground, or battery ground, the directional circuit thereby developing a DC potential in response to the alternating electric field which is self referencing between a relatively high potential output and a relatively lower potential output. One or more loads connected to the directional circuit, the one or more loads also not having a continuous conductive path to earth ground or a battery ground. The load is not provided with a continuous connection to earth ground, or battery ground.

A circuit and method for starting up a band-gap reference circuit. In one example, a startup circuit compares a Vbg voltage output of a band-gap reference circuit to a voltage (such as Vbe) across a transistor in order to selectively control whether to inject current into the band-gap reference circuit during startup.

The invention belongs to the technical field of power supplies, and discloses a band-gap voltage reference source for high-order temperature compensation, which specifically comprises a starting circuit, a first-order band-gap reference circuit, a high-order temperature compensation circuit and a summation output circuit. The band-gap voltage reference source works out the reference voltage by summating the first-order band-gap reference voltage which is generated by the first-order band-gap reference circuit and the voltage which is converted from the high-order temperature compensation current which is generated by the high-order temperature compensation circuit, and improves the temperature coefficient of the band-gap reference voltage source by introducing index compensation; the designed circuit simultaneously adopts two feedback loops, so that the power supply rejection ratio (PSRR) and the linear adjustability are improved; and simultaneously, because the low-voltage working requirement is met, the voltage reference source has a very wide scope of application.

A linear voltage regulator with ultralow differential voltage and strong driving capacity is based on a circuit which consists of a drive circuit (Buffer), a feedback network with resistance voltage division, an error amplifier, a reference circuit and a load. The linear voltage regulator is characterized by further comprising an NMOS output tube and a forward voltage boosting charge pump circuit, wherein, the NMOS output tube is configured for receiving a voltage signal output by the drive circuit (Buffer) and providing corresponding current to the load; and the forward voltage boosting charge pump circuit is configured for receiving a voltage signal VIN from other than the linear voltage regulator and supplying power to the drive circuit (Buffer). The linear voltage regulator is especially suitable for occasions that input voltage and output voltage are close to each other, and can provide relatively strong driving capacity, thus obviously improving efficiency. The linear voltage regulator has the advantages of saving chip area, lowering cost and having very strong practicability on the premise of ensuring two performances of low voltage drop and strong driving capacity.