212 results about "Diode voltage" patented technology

A temperature measurement device may be implemented by coupling a PN-junction, which may be comprised in a diode, to an analog-to-digital converter (ADC) that comprises an integrator. Different currents may be successively applied to the diode, resulting in different VBE values across the diode. The ΔVBE values thus obtained may be successively integrated. Appropriate values for the different currents may be determined based on a set of mathematical equations, each equation relating the VBE value to the temperature of the diode, the current applied to the diode and parasitic series resistance associated with the diode. When the current sources with the appropriate values are sequentially applied to the diode and the resulting diode voltage differences are integrated by the integrator comprised in the ADC, the error in the temperature measurement caused by series resistance is canceled in the ADC, and an accurate temperature reading of the diode is obtained from the output of the ADC.

Systems and methods to achieve a circuit for driving one or more infrared transmitter LEDs with temperature compensation have been disclosed. In a preferred embodiment of the invention the circuit has been applied for a rain sensing system. The junction temperature of the LED is measured and compensated by adjusting the driver current of a voltage-to-current converter driving the LED. The LED junction temperature is measured by comparing the difference in the forward diode voltage at different current densities. This voltage difference is extracted when switching the drive currents between different constant values. The measurement results are converted to digital values, which are used by a buffered dual ladder resistive DAC structure to adjust the drive current to temperature variations.

A temperature sensor circuit and system providing accurate digital temperature readings using a local or remote temperature diode. In one set of embodiments a change in diode junction voltage (ΔVBE) proportional to the temperature of the diode is captured and provided to an analog to digital converter (ADC), which may perform required signal conditioning functions on ΔVBE, and provide a digital output corresponding to the temperature of the diode. DC components of errors in the measured temperature that may result from EMI noise modulating the junction voltage (VBE) may be minimized through the use of a front-end sample-and-hold circuit coupled between the diode and the ADC, in combination with a shunt capacitor coupled across the diode junction. The sample-and-hold-circuit may sample VBE at a frequency that provides sufficient settling time for each VBE sample, and provide corresponding stable ΔVBE samples to the ADC at the ADC operating frequency. The ADC may therefore be operated at its preferred sampling frequency rate without incurring reading errors while still averaging out AC components of additional errors induced by sources other than EMI.

A voltage booster and regulator usable with Dickson-type charge pump device is specifically adapted to maintain efficiency with both high and low supply voltages. For high voltage supplies (e.g., 2.6 volts or more), the charge pump reduces overall power consumption resulting in a more efficient design. For low voltage applications (e.g., for supply voltages less than 2.6 volts), the charge pump uses a booster circuit to increase a clock input potential beyond the supply voltage available to a typical Dickson array. Further, the charge pump avoids inherent diode voltage drops in a typical Dickson array.

Methods and apparatus are provided for varying one or more of a supply voltage and reference voltage in an integrated circuit, using independent control of a diode voltage in an asymmetrical double-gate device. An integrated circuit is provided that is controlled by one or more of a supply voltage and a reference voltage. The integrated circuit comprises an independently controlled asymmetrical double-gate device to adjust one or more of the supply voltage and the reference voltage. The independent control may comprise, for example, a back gate bias. The independently controlled asymmetrical double-gate device may be employed in a number of applications, including voltage islands, static RAM, and to improve the power and performance of a processing unit.

The present invention provides a primary-side regulated PWM (pulse width modulation, pulse width modulation) controller with improved load regulation. In each PWM cycle, a built-in feedback voltage generator samples and holds the flyback voltage from the auxiliary winding of the transformer through a sampling switch, and generates a feedback voltage accordingly. A bias current sink sinks a bias current proportional to the feedback voltage. When the output load changes, the bias current will generate a voltage drop through a sense resistor to compensate the voltage drop of the output rectifier diode. According to the present invention, the bias current may enable the PWM controller to regulate the output voltage very accurately without using a secondary feedback circuit.

The invention relates to a DC / DC converter including an input to which an input voltage Vin is applied, a inductance L whose one terminal is connected to the input, a first controllable switch N1 via which the other terminal of the inductance is connectable to a reference potential Vss, a second controllable switch P1 via which the other terminal of the inductance is connectable to the output of the converter, and a regulator circuit 1 configured so that it is able to control the two switches in regulating the output voltage of the DC / DC converter to a predetermined wanted value. The second controllable switch is a PMOS-FET. The regulator circuit is configured so that when the input voltage is higher than the desired value of the output voltage, the gate of the PMOS-FET is permanently connected to a voltage which is larger than the difference between the input voltage and the threshold voltage of the PMOS-FET, it connecting the back gate of the PMOS-FET permanently to a voltage which is larger than the expression input voltage plus threshold voltage of the PMOS-FET minus the diode voltage of a pn junction of the PMOS-FET and timing the first controllable switch with a specific duty cycle so that the output voltage attains the wanted value. The converter in accordance with the invention now permits achieving both an increase and decrease in the input voltage. It can be put to use preferably in conjunction with battery-powered devices for which a wanted voltage is specified.

The invention discloses a Buck circuit multiparameter on-line identification method. The method comprises the steps that firstly, the Buck circuit is analyzed according to the Kirchhoff's law, and a state-space equation set of the Buck circuit is set up; secondly, according to the state-space equation set, a local linear model of the Buck circuit is set up; thirdly, according to the local linear model, a measurement matrix and a parameter matrix are defined; fourthly, different parameter values, monitoring inductive currents, output voltages and diode voltage signals of different elements in the Buck circuit are set; fifthly, estimated valve of the parameter matrix is obtained through least squares recursive algorithm. The parameter matrix obtained from the above estimated valve is used to calculating the parameter valves of the element need to be identified. According to the Buck circuit multiparameter on-line identification method, the influence of the diode and diode pre-stage circuit parameters including a non-ideal voltage and an input voltage on the precision of the parameter identification is removed, the practical operation is easy to achieve, and the identification precision is higher.

The invention relates to a method for testing thermal resistance of a high-power silicon carbide diode, which comprises the following steps: putting an insulation substrate with a device to be tested in a temperature-controlled cabinet, regulating the temperature of the temperature-controlled cabinet to 25 DEG C, applying a transient monopulse current to the diode, and testing the diode voltage drop corresponding to different pulse current magnitudes; heating the temperature-controlled cabinet to 125 DEG C, measuring the diode voltage drop corresponding to different pulse current magnitudes, comparing with the values measured at 25 DEG C, and taking a maximum current on the premise of ensuring obvious change of voltage drop; dropping the temperature of the temperature-controlled cabinet to 25 DEG C, applying a direct current with the magnitude selected above to the diode, and measuring the diode voltage drop after the junction temperature becomes stable; changing the temperature of the temperature-controlled cabinet, and testing the diode voltage drop at this time by using pulse current until the diode voltage drop at a certain temperature is equal to the diode voltage drop when applying the direct current, thus, the temperature of the temperature-controlled cabinet at this time is the equivalent junction temperature; and computing the thermal resistance of the diode according to the equivalent junction temperature by using a thermal resistance computing formula.

The invention discloses a ultra-low power consumption voltage detection circuit, which comprises an MOS diode voltage-dividing network, a level detection circuit and an output logic circuit. The main function of the MOS diode voltage-dividing network is to perform continuous sampling on a voltage to be detected, and provide a base input voltage and a base input current for an NPN triode in the level detection circuit; the level detection circuit is the core part of the ultra-low power consumption voltage detection circuit and utilizes the basic idea of band-gap reference, can realize accurate detection on the voltage to be detected under the condition that a reference voltage is not needed, and a voltage detection point has good temperature characteristics; and the output logic circuit is used for shaping a detection output signal at last. Compared with the traditional voltage detection technology, the ultra-low power consumption voltage detection circuit can operate at ultra-low power consumption (tens of nW) without an extra datum reference voltage, is low in area cost, and is very suitable for chip fields of radio frequency identification electronic tags, dual-interface intelligent cards and the like.

A band-gap reference circuit is compensated for temperature dependent curvature in its output. A voltage across a diode with a fixed current is subtracted from a voltage across a diode with a proportional to absolute temperature (PTAT) current. The resultant voltage is then magnified and added to a PTAT voltage and a diode's voltage that has a complementary-to-absolute temperature (CTAT) characteristic, resulting in a curvature corrected hand-gap voltage. This allows for the band-gap reference circuit to be trimmed at a single temperature. This allows the circuit to be made with only a single trimmable parameter, which, in the exemplary circuits, is a resistance value.

Provided is a temperature-compensated circuit for a power amplifier through diode voltage control, in which a first resistor (Rref), a first diode (D1), and a second diode (D2) are connected to a reference voltage in series. The temperature-compensated circuit includes a second resistor (R1) connected to the reference voltage, a third resistor (R2) connected to the second resistor in series, a fourth resistor (Rc) having one terminal connected to the reference voltage, a fifth resistor (Re) having one terminal connected to ground, a bias transistor having a base terminal connected to a contact point (VS) between the second resistor and the third resistor, a collector terminal connected to the other terminal of the fourth resistor, and an emitter terminal connected to the other terminal of the fifth resistor, and a sixth resistor (Rf) connected between a series connection terminal between the first diode and the second diode, and the collector terminal of the bias transistor. The voltage of the collector terminal changes for compensation of a temperature.