摘要:
A fully integrated DC-DC converter utilizes digitally controlled dual output stages to achieve fast load transient recovery is presented. The DC-DC converter includes a main converter output stage connected in parallel with an auxiliary output stage. The main output stage is responsible for steady-state operation and is designed to achieve high conversion efficiency using large inductor and power transistors with low on-resistance. The auxiliary stage is responsible for transient suppression and is only active when a load transient occurs. The auxiliary output stage performs well with inductor and power transistors much smaller than those of the main switching stage and thus achieves well balanced power conversion efficiency and dynamic performance with a much smaller area penalty than previously described dual-output-stage converters.
摘要:
A switching power supply system controlling switching operations of switching devices by a control circuit to convert an input voltage into a desired output voltage, the system being provided with a under voltage lock out circuit including: an input voltage detection unit detecting an input voltage and producing an input voltage digital signal corresponding to the input voltage Vin; and a voltage level comparison unit carrying out digital comparison of the input voltage digital signal with each of two voltage detection level data and outputting the results of the comparisons as an output signal, in which by changing voltage detection level data stored in two registers, desired voltage detection levels and hysteresis characteristic are easily actualized.
摘要:
A switching power supply that can suppress output variation at a time of transition of a control mode from a non-linear control mode to a linear control mode. The switching power supply includes instruction value forming circuitry that forms, in a linear control mode, a linear control instruction value for linearly control a switching circuit based on an error of an output voltage, and forms, in a non-linear control mode, a non-linear control instruction value for non-linearly control the switching circuit. The instruction value forming circuitry predicts, in the non-linear control mode, a linear control instruction value suited to the load current in the non-linear control mode, and uses the predicted linear control instruction value for an initial value of the linear control instruction value at a time of transition from the non-linear control mode to the linear control mode.
摘要:
A digital control switching power supply unit includes an A/D converter circuit having a delay line circuit that has a delay element array whose delay time is controlled by a bias current, and that converts a current value into a digital signal using a signal transmission delay time, a phase difference detector circuit that detects a phase difference between a switching cycle and an A/D conversion cycle, a charge pump circuit that generates a control voltage in accordance with the phase difference, and a bias current indicator circuit that determines a bias current in accordance with an output voltage of the charge pump circuit and a result of a comparison of a detected value of the output voltage and a reference voltage, wherein the digital control switching power supply unit controls in such a way that the A/D conversion cycle is synchronized with the switching cycle.
摘要:
A digital control switching power supply unit converts an input voltage into a desired output voltage using a digitally controlled pulse width modulation (PWM) signal according to a switching cycle. The power supply unit includes an analog-to-digital converter (ADC). The ADC converts a result of a comparison between an output voltage and a reference voltage to a digital signal during a conversion cycle. The ADC includes a circuit for outputting a phase difference between a switching cycle and the conversion cycle, and a delay circuit. The delay circuit generates a delay output current based on a result of the comparison and the phase difference and determines the conversion time delay according to the delay output current. The delay circuit also generates a delay reference current based on the reference voltage and the phase difference and determining the duration of the conversion cycle according to the delay reference current.
摘要:
A digital control switching regulator of the invention ON/OFF-controls switching elements by digital-controlled pulse width modulation signals and converts an input voltage to a desired output voltage. The switching regulator includes an input voltage detection circuit that includes: a voltage dividing circuit outputting a divided voltage of the input voltage; a comparator section comparing the divided voltage of the input voltage with a first reference voltage and a second reference voltage and outputting a first comparison signal and a second comparison signal indicating comparison results; and a control section controlling a dividing ratio of the voltage dividing circuit based on the first comparison signal and the second comparison signal to obtain the predetermined divided voltage, thereby outputting an input voltage digital signal corresponding to the input voltage. The input voltage digital signal controls controller coefficients for use in the digital control.
摘要:
A switching power supply that can suppress output variation at a time of transition of a control mode from a non-linear control mode to a linear control mode. The switching power supply includes instruction value forming circuitry that forms, in a linear control mode, a linear control instruction value for linearly control a switching circuit based on an error of an output voltage, and forms, in a non-linear control mode, a non-linear control instruction value for non-linearly control the switching circuit. The instruction value forming circuitry predicts, in the non-linear control mode, a linear control instruction value suited to the load current in the non-linear control mode, and uses the predicted linear control instruction value for an initial value of the linear control instruction value at a time of transition from the non-linear control mode to the linear control mode.
摘要:
A potentiometric titration method including calculating a titration curve and a differential curve from measured values; computing a straight line (D) connecting the two measured values on the titration curve which are present adjacent to a tentative terminal point (P); computing a first estimation line (B1) and a second estimation line (B2) by a least squares method based on a set of the measured values (d1), (d2) and (d3) and a set of the measured values (d4), (d5) and (d6), respectively, on the titration curve, which are respectively spaced by a predetermined level apart from the tentative terminal point (P) by using the number of decision points (n) as an index where the number of decision points (n) represents the number of measured values on the previously set titration curve; computing an intermediate line (C) between the first estimation line (B1) and the second estimation line (B2); and computing an intersection point (A) of the intermediate line (C) and the straight line (D) to read out a value of the intersection point on an abscissa axis as a terminal point (a) of the titration.
摘要:
There is proposed a control unit for an internal combustion engine, which comprises a boost circuit, a switching element, a current detecting resistor and a controller and is designed to be actuated such that the boost circuit is used to boost a power source voltage to create a boosted voltage and the controller is used to control the switching element so as to enable the boosted voltage to flow to the injector solenoid coil. This control unit is designed such that, when the boost circuit goes out of order, the injector solenoid coil is excited by making use of the power source voltage without using the boosted voltage and without creating a peak current to thereby generate a first holding current required for opening the injector and a second holding current required for retaining the opened state of the injector, the second holding current being lower in intensity than the first holding current.
摘要:
To provide an apparatus that may impart a complicated bend deformation to an object to be machined such as a ceramic bar elongated in one direction or the like, and may reduce the non-uniformity in machining amount of the object to be machined upon the machining work of the object to be machined, specifically a correcting mechanism for deforming the object to be machined together with a jig holding the object to be machined is provided in a machining apparatus. The correcting mechanism includes a base, a plurality of levers provided at first ends with pins, a shaft fixed to the base for rotatably supporting the levers, and a plurality of correcting drive means coupled to second ends of said levers for pivoting the levers to the shaft to thereby pivoting the pins. The jig includes a plurality of load receiving portions arranged in a holding portion elongated on one direction for holding the object to be machined whereby portions corresponding to the load receiving portion in the holding portion are deformed together with the object to be machined in accordance with pivoting of each pin.