1591 results about "Reference level" patented technology

Exemplary embodiments provide a system, method and appartus for regulating current in loads, such as in an array of independent pluralities of light emitting diodes (“LEDs”). An exemplary system comprises a multiplexer adapted to switch current to each independent string of LEDs; a first controller to maintain a substantially constant average current level to the plurality of LEDs; and a second controller to modulate a current amplitude and duration of time division multiplexing for each independent string of LEDs. Another aspect of the system provides for modulating the on time for switching current to maintain a substantially constant average current level and to respond and converge quickly to changing current reference levels.

A circuit and a method for controlling output current of cascaded switching power converters having a buck type output stage are disclosed. The circuit comprises two comparators for sensing input and output current, a logic gate for processing the output states of the comparators, and a pulse width modulator circuit for receiving the output of the logic gate and for controlling a switching power converter in accordance with this output. The method comprises simultaneous monitoring current in the stages of the converter, comparing the currents to the corresponding reference levels, generating the corresponding error signals, and controlling a pulse-width modulator circuit of a switching converter in accordance with these error signals.

A vehicle preferential treatment system includes a controller mounted in a hybrid vehicle, and a server performing wireless communications with the controller. The controller estimates an SOC of an electric storage (not shown) and transmits the SOC to the server. When the SOC of the electric storage exceeds a reference level, the server gives a preferential treatment to the hybrid vehicle. Then, information on the preferential treatment is transmitted from the server to the controller, and is displayed on a display unit of the controller.

The present invention presents several techniques for using writable tracking cells. Multiple tracking cells are provided for each write block of the memory. These cells are re-programmed each time the user cells of the associated write block are written, preferably at the same time, using the same fixed, global reference levels to set the tracking and user cell programmed thresholds. The threshold voltages of the tracking cells are read every time the user cells are read, and these thresholds are used to determine the stored logic levels of the user cells. In one set of embodiments, populations of one or more tracking cells are associated with different logic levels of a multi-state memory. These tracking cell populations may be provided for only a subset of the logic levels. The read points for translating the threshold voltages are derived for all of the logic levels based upon this subset. In one embodiment, two populations each consisting of multiple tracking cells are associated with two logic levels of the multi-bit cell. In an analog implementation, the user cells are read directly using the analog threshold values of the tracking cell populations without their first being translated to digital values. A set of alternate embodiments provide for using different voltages and/or timing for the writing of tracking cells to provide less uncertainty in the tracking cells' final written thresholds.

A charging monitor has: a switch that is disposed between a load section having a storage battery and an external AC power supply supplying a current to the load section via a plurality of lines and interrupts the supply of the current from the external AC power supply to the load section; a current detection circuit that outputs a detection signal corresponding to a difference in level between currents flowing through the lines; a suppression circuit that suppresses a DC component contained in the detection signal; a filter circuit that filters a plurality of frequency components contained in the detection signal so that attenuation increases as a frequency becomes high; a rectifier smoothing circuit that rectifies and smoothens an output signal obtained when the detection signal passes through the filter circuit and the suppression circuit; and an electric leakage determination circuit that detects an electric leakage and shuts off the switch when the level of the signal smoothened by the rectifier smoothing circuit exceeds a preset reference level.

A solid-state image sensor includes a pixel array unit including a plurality of pixels arranged in the form of an array, column signal lines adapted to transmit pixel signals output from pixels in respective columns, a noise adding unit adapted to add temporally constant and two-dimensional spatially random noise to the pixel signals transmitted via the column signal lines, and an analog-to-digital converter adapted to convert a signal level and a reference level of each pixel signal including the noise added thereto by the noise adding unit.

Provided is a detector system for detecting a plurality of items each having at least one RFID tag attached thereto. The detector system may include a presence detector and/or a message detector. The presence detector may include a signal reader which receives modulated carrier frequencies from the RFID tags during a predetermined response time period for comparison to a reference level. The signal reader may be configured as a power integrator or a constellation discriminator. The power integrator sums the power contained in signals transmitted by the RFID tags by integration for comparison to an environmental noise level measurement taken during a quiet period. For the constellation discriminator, bits contained in the modulating message are compared to the bit pattern of a predetermined reference constellation. The detector system may be configured as a 3-state detector which combines the presence detector with a message detector that indicates the identification code of the RFID tags.

The present invention relates to an apparatus and method for acquiring an image for iris recognition using a distance of a facial feature, the apparatus comprising: a buffer for photographing one or more facial images of a subject being photographed so as to acquire an image for iris recognition and storing the photographed facial images; a facial feature distance calculating unit for calculating a distance of a facial feature from the facial images stored in the buffer; an actual distance estimating unit for estimating an actual distance between the subject being photographed and a camera from the distance of the face feature calculated by the facial feature distance calculating unit, and confirming, from of the estimated distance, that the subject being photographed exists in an iris photographing space; and an iris image acquiring unit for acquiring an eye image from the facial images of the subject being photographed that has been confirmed as existing in the iris photographing space by the actual distance estimating unit, and measuring the quality of the acquired eye image so as to acquire an image for iris recognition, which satisfies a reference level of quality.

A DC—DC converter can supply a stable output voltage from an input voltage with the power supply voltage varying along with the supply of the power and can maintain a high voltage conversion efficiency. The DC—DC converter includes an inductive element and the first-fourth switches connected to both terminals of the inductive element, the first and second switches are turned on and off periodically corresponding to the input voltage. When the input voltage goes below a prescribed reference level, a first control signal that keeps the first switch constantly on is generated by a feedforward control circuit to turn on the third and fourth switches periodically corresponding to the output voltage so that the output time of the third switch is generated by a feedback control circuit to switch the voltage increasing operation and the voltage increasing/decreasing operation corresponding to the input voltage.

The invention provides methods for determining a prognosis for survival for a cancer patient. One method involves (a) measuring a level of a TUCAN in a neoplastic cell-containing sample from the cancer patient, and (b) comparing the level of TUCAN in the sample to a reference level of TUCAN, wherein a low level of TUCAN in the sample correlates with increased survival of the patient. Another method involves (a) measuring a level of TUCAN in a neoplastic cell-containing sample from the cancer patient, and (b) classifying the patient as belonging to either a first or second group of patients, wherein the first group of patients having low levels of TUCAN is classified as having an increased likelihood of survival compared to the second group of patients having high levels of TUCAN.

In a solid-state image sensing element which includes a pixel array portion in which a plurality of pixels each including a photoelectric converter are arranged two-dimensionally, and readout circuits which read out analog pixel signals from the pixel array portion by column, and in which each of the readout circuits includes an A/D conversion circuit which converts the analog pixel signal from the pixel array portion into a digital pixel signal, and the A/D conversion circuit performs A/D conversion by comparing, by a comparison unit, a signal level of the analog pixel signal from the pixel array portion with a temporally changing reference level, a frequency band characteristic of the comparison unit is switched in accordance with the signal level of the analog pixel signal from the pixel array portion.

System and method for wireless channel sensing. According to an embodiment, the present invention provides a method of determining band availability for a WRAN. The method includes receiving wirelessly analog signals within a predetermined range of frequencies. The method also includes converting the analog signals to digital signals. The digital signals are characterized in a frequency domain. The method additionally includes determining a plurality of signal strength levels associated with the digital signals at a plurality of frequencies. Furthermore, the method includes comparing the plurality of signal strength levels to reference levels at the plurality of frequencies. Moreover, the method includes determining band availability for wireless communication at the predetermined range of frequencies.

A data read circuit and method for use in a semiconductor memory device that has a memory cell array are provided. The circuit includes a selector for selecting a unit cell within the memory cell array in response to an address signal; a clamping unit for supplying a clamp voltage having a level for a read operation to a bit line of the selected unit cell in response to a clamp control signal; a precharge unit for precharging a sensing node to a voltage having a power source level in response to a control signal of a first state in a precharge mode, and compensating through the sensing node for a reduced quantity of current at the bit line in response to a control signal of a second state in a data sensing mode; and a sense amplifier unit for comparing a level of the sensing node with a reference level, and for sensing data stored in the selected unit cell.

In a communication system, a first wireless communication apparatuses belonging to a communication group receives a connection request frame including a notifying security level from a second communication apparatus outside of the communication group. The first communication apparatus stores a reference security level peculiar to the communication group, which is selected from security levels depending on one of encryption methods including non-encryption and encryption strengths. In the first communication apparatus, the notifying security level is compared with the reference level, and a response frame including one of a connect rejection and a connection permission is described, is generated and transferred to the second communication apparatus. The connect rejection represents a rejection of connection to the second communication apparatus and the connection permission represents a permission of connection to the second communication apparatus.