Showing papers on "Voltage multiplier published in 2003"

Fully integrated passive UHF RFID transponder IC with 16.7-/spl mu/W minimum RF input power

Abstract: This paper presents a novel fully integrated passive transponder IC with 4.5- or 9.25-m reading distance at 500-mW ERP or 4-W EIRP base-station transmit power, respectively, operating in the 868/915-MHz ISM band with an antenna gain less than -0.5 dB. Apart from the printed antenna, there are no external components. The IC is implemented in a 0.5-/spl mu/m digital two-poly two-metal digital CMOS technology with EEPROM and Schottky diodes. The IC's power supply is taken from the energy of the received RF electromagnetic field with help of a Schottky diode voltage multiplier. The IC includes dc power supply generation, phase shift keying backscatter modulator, pulse width modulation demodulator, EEPROM, and logic circuitry including some finite state machines handling the protocol used for wireless write and read access to the IC's EEPROM and for the anticollision procedure. The IC outperforms other reported radio-frequency identification ICs by a factor of three in terms of required receive power level for a given base-station transmit power and tag antenna gain.

Step-up switching-mode converter with high voltage gain using a switched-capacitor circuit

Abstract: A new circuit is proposed for a steep step-up of the line voltage. It integrates a switched-capacitor (SC) circuit within a boost converter. An SC circuit can achieve any voltage ratio, allowing for a boost of the input voltage to high values. It is unregulated to allow for a very high efficiency. The boost stage has a regulation purpose. It can operate at a relatively low duty cycle, thus avoiding diode-reverse recovery problems. The new circuit is not a cascade interconnection of the two power stages; their operation is integrated. The simplicity and robustness of the solution, the possibility of getting higher voltage ratios than cascading boost converters, without using transformers with all their problems, and the good overall efficiency are the benefits of the proposed converter.

An interleaved boost DC-DC converter with large conversion ratio

Abstract: A new PWM dc-dc converter is introduced in which large voltage step-up ratios can be achieved without high duty-cycle, with low voltage and current stress and without transformer. The proposed circuit is an extension of the boost interleaved converter, incorporating a multistage capacitor multiplier. A simple nondissipative snubber can be used reducing the reverse recovery current of the diodes and also obtaining low turn-on and turn-off losses. The modularity of the structure allows the increment of the current, voltage and power levels, using the same range of components and maintaining high efficiency, only increasing the number of series and parallel stages. The paper gives a theoretical analysis, and experimental data on a 400 W example that was built and tested: 24 Vdc input, 200 Vdc output, and 40 kHz switching frequency. The measured performance agreed well with the theoretical predictions and the measured efficiency obtained is equal to 95% at full load.

Variable charge pump circuit with dynamic load

Abstract: A variable charge pump circuit (300) uses a plurality of selectable loads (322, 326, 330; Figs. 5A-5B) to minimize the voltage ripples of the pumped output (334) by selecting the appropriate load for a preselected pump voltage (Vout). The charge pump circuit also compares the pump voltage to a reference voltage (Vref) to shut down the variable charge pump circuit if the pump 10 voltage is larger than the reference voltage. The charge pump circuit also compares the maximum voltage output to the reference voltage to monitor whether the maximum ripple on voltage output is larger than the reference voltage. The charge pump circuit comprises one or more stages (306, 310; 308, 312) operable to receive a supply voltage (Vcc) and generate one or more pump voltages, a plurality of loads (322, 326, 330) each associated with a specific pump voltage, and a load selector means (320, 324, 328) coupled to the output pump and to the plurality of loads for selecting a load associated with a specific pump voltage.

A new high static gain nonisolated DC-DC converter

Abstract: A new high efficiency transformerless dc-dc converter is proposed in which large step-up ratios can be achieved with low duty cycle. The proposed structure integrates a multiphase voltage multiplier that allows to obtain high static gain with low voltage stress in all semiconductors. The interleaved technique is also used, allowing the operation of the multiplier stages and also reducing the current stress in all components. The input inductors and output capacitor are reduced by the interleaved operation. The modularity of the structure allows the increment of the current, voltage and power levels, using the same range of components and maintaining high efficiency, only increasing the number of series and parallel stages. A laboratory prototype with P/sub 0/=400 W and V/sub in/=24 V was built and tested. Two configuration was implemented operating with V/sub 0/=200 V and V/sub 0/=400 V. The performance agreed well with the theoretical predictions and the measured efficiency obtained when operating with nominal load is equal to 95 %.

High-voltage power supply

Abstract: A high-voltage power supply (10) includes: a power scaling section (130) that receives an input voltage signal and converts the input voltage signal to a controllable DC voltage; a push-pull converter (140) for converting the controllable DC voltage to a high-frequency wave; and a voltage multiplier (200) receiving the high-frequency wave generated by the push-pull converter (140) and performing successive voltage doubling operations to generate a high-voltage DC output In one implementation, the voltage multiplier (200) receives a square wave having a frequency of approximately 100kHz and outputs an adjustable DC voltage of approximately 0-to-30kV In one implementation, the high-voltage power supply (10) includes an insulation system (250) for the voltage multiplier module (200), such an insulation system being formed on n insulating layers and m conducting strips positioned between successive insulating layers

PLL with built-in filter-capacitor leakage-tester with current pump and comparator

Abstract: A filter capacitor within a phase-locked loop (PLL) can be tested using a built-in test circuit. The PLL's charge pump is deactivated while a test-current source is activated to supply a test current to the PLL filter capacitor. When the test current is larger than any leakage currents through the capacitor, the capacitor's voltage rises above a reference voltage. A test comparator compares the capacitor's voltage to the reference voltage and signals a good test result when the capacitor's voltage rises above the reference voltage. When leakage current is larger than the test current, the capacitor's voltage cannot rise above the reference voltage and the test comparator signal a leakage failure. The test current source can share a bias voltage with the charge pump and can drive the capacitor to a voltage higher than the charge pump does to increase leakage and stress during testing.

High voltage ripple reduction and substrate protection

Abstract: In a non-volatile memory, charge pumps are used to provide high voltages needed for programming memory cells that have floating gate structures. Charge pumps have a series of voltage multiplier stages in series to boost voltage. These charge pumps must rapidly charge a load to a high voltage and then maintain a voltage with a high degree of stability. Techniques for achieving both of these goals are presented. In one aspect, a charge pump has two operating states, one to charge a load rapidly and a second to maintain a voltage on a charged load with high stability. These states are achieved by changing the current output from a high current during charging to a low current to maintain the voltage. This is done by changing the capacitance used in the individual voltage multiplier stages. In another aspect, two different current levels are produced by changing the voltage used to charge the capacitors of the voltage multiplier stages.

A linear high voltage charge pump for MEMs applications in 0.18/spl mu/m CMOS technology

Abstract: Tunable MEMS components start to appear in wireless communication systems. They allow for new functionality such as tunable RF filters or they improve performance like electrostatically tuned variable capacitors that are used in voltage-controlled oscillators. However, the required tuning voltage for these capacitors is often much higher than the supply voltage of these capacitors is often much higher than the supply voltage of the deep sub-micron (Bi)CMOS technology which is typically used for these applications. Therefore we designed a high voltage charge pump that can generate an output voltage between -0.7V and +14.8 V out of a 1.8 V power supply. It is built in a 0.18 /spl mu/m CMOS technology, requires the same control signals as a regular charge pump and provides a constant output current of 0.7/spl mu/A over its complete voltage range of MEMS variable capacitors at low power, at a small area cost and in a way which is completely transparent to the system designer.

Switched capacitor voltage reference circuits using transconductance circuit to generate reference voltage

Abstract: A switched capacitor voltage reference circuit that has a transconductance circuit that receives the output of the amplifier, and then outputs a current that depends on its input voltage. This may be accomplished using a charge pump that is controlled by the amplifier output. The transconductance circuit provides a reference voltage at the output terminal of the switched capacitor generation circuit. A capacitor capacitively couples the output terminal of the switched capacitor circuit to the inverting terminal of the amplifier during the generation phase. By adjusting the capacitances of the various capacitors, the level and temperature dependence of the generated reference voltage may be controlled. Also, the charge pump often allows for reference voltages that are greater than the supply voltage.

Electroluminescent display apparatus and driving method thereof

Abstract: A common line is eliminated, and one terminal of the capacitor, which has been heretofore connected to the common line, is connected to the scan line of another display cell adjacent to the display cell having the capacitor. A scan line driving circuit supplies to respective scan lines a stepped pulse formed of a voltage V 1 and a voltage V 2 sufficiently larger than the voltage V 1. A data line driving circuit supplies to the respective data lines a voltage not smaller than the voltage V 1 and not larger than a voltage V 3 (but smaller than the voltage V 2 ) as a data voltage.

Constant voltage discharge device

Abstract: Circuits and methods for supplying a temporary power supply at a predetermined voltage are disclosed. A circuit includes first DC/DC voltage that receives an input from a power supply at a first voltage level and generates an output at a second voltage level, higher than the first voltage level. The output is provided to charge a capacitor. A second DC/DC voltage converter has an input connected to the capacitor for drawing power from the capacitor at the second voltage level and an generates an output voltage less than the second voltage level. The second DC/DC voltage converter further includes a feedback input that monitors the circuit's output voltage and activates the second DC/DC voltage converter when the output voltage falls below a predetermined threshold.

Signal derived bias supply for electrostatic loudspeakers

Abstract: An electrostatic loudspeaker requires a high voltage DC bias power supply to bias the stators and diaphragms of electrostatic speakers. A self biased power supply eliminates the need for an external power supply by deriving a high voltage bias from the stator AC signal voltages which have been rectified and run from a high voltage tap and/or through a voltage multiplier which has a voltage limiting means.

Use of track lighting switching power supplies to efficiently drive LED arrays

Abstract: A power conditioning circuit is coupled between a conventional low-voltage 12 volt AC switching power supply used in track lighting arrangements and an LED array used for illumination of an area. A conventional voltage multiplier is provided having a low input impedance for producing a current inrush from the switching power supply, sufficient in magnitude and duration to excite the low-voltage switching supply in spite of the low LED load to be energized. The resulting voltage multiplied and rectified current is fed to a precise DC voltage regulator for very efficiently driving an array of series-parallel strings of light emitting diodes. The use of the voltage multiplication combined with precise DC voltage regulation feature enables driving LED arrays having the longest possible light emitting diode serial strings for the available voltage, increasing energy efficiency while keeping the circuit near ambient temperature.

A high-voltage bi-polar pulse generator a using push-pull inverter

Abstract: In this paper, a fast high voltage bi-polar pulse generator using push-pull inverter is proposed. The proposed pulse system consists of a thyristor rectifier, a DC link, a push-pull resonant inverter, a high voltage transformer, a secondary capacitor, a high voltage IGBT and diode stack, and a variable capacitor. The proposed system generates bi-polar high voltage sinusoidal waveform using resonance between the leakage inductance of the transformer and the secondary capacitor and transfers energy to output load at the maximum level of the secondary capacitor voltage. Compared to the previous bi-polar high voltage pulse power supplies using nonlinear transmission line, the proposed pulse power system has dominant advantages, such a flexibilities of output voltage (pulse width, PRR, and pulse rising time) and high efficiency due to the use of only semiconductor switches. The theoretical operational principle will be described in detail and key experimental results will be provided to verify the validity of the proposed system.

Negative voltage output charge pump circuit

Abstract: In a negative voltage output charge pump circuit, first a capacitor C 1 is charged with a positive voltage Vin relative to a reference voltage, and then the high-potential terminal A of the capacitor C 1 is made to conduct to the reference voltage and simultaneously the low-potential terminal B of the capacitor C 1 is made to conduct to an output terminal OUT so that the voltage with which the capacitor C 1 is charged is output as a negative voltage −Vin. Here, at least one of the switching device DP 1 that is kept on while the capacitor C 1 is being charged so as to apply the reference voltage to the point B and the switching device DP 2 that is kept on while the negative voltage is being output so as to make the point B conduct to the output terminal OUT is a depletion-type transistor. This configuration makes it possible to realize a negative voltage output charge pump circuit that is free from malfunctioning caused by a parasitic device, that operates with low loss, and that can be produced at low costs.

Highly efficient, high current drive, multi-phase voltage multiplier

Abstract: The highly efficient, high current drive, multi-phase voltage multiplier reduces the inefficiency due to the active level overlapping portion of the clock at high frequencies, reduces the inefficiency due to extremely large drive currents on the inverters supplying current to the multiplying capacitors C 1 (*) and C 2 (*), and increases the efficiency of the multiplier by allowing M-1 phases to charge the output at any given time and providing more time given to each capacitor to fully charge and discharge. The ripple on the output is much smaller than in a single dual phase multiplier. This multi-phase voltage multiplier supplies very large current to the load while remaining very efficient.

Device to provide a regulated power supply for in-cylinder ionization detection by using a charge pump

Abstract: A charge pump is used to supply current to the ionization detection circuit To detect in-cylinder ions generated during the combustion process, a DC bias voltage needs to be applied There are two ways to generate the DC bias: conventional DC power supply (large electronics) and capacitor charges by primary or secondary flyback voltage (high voltage capacitor) Typically, flyback voltage is used to charge the capacitor which supplies current to the ionization detection circuit This necessitates the use of high voltage capacitors Generally, ceramic capacitors are used However, as temperature fluctuates, the board that the capacitor is mounted on can flex, causing the ceramic capacitor to crack This invention proposes to use a high voltage charge pump to provide enough DC bias voltage for measuring ionization current In a preferred embodiment, a model number M1C4827 EL driver is used in the charge pump circuit The charge pump circuit will convert the 12 Volt DC at the B+ terminal to a 90 to 100 volt pulse train with a pulse repetition frequency of 500 kHz at the charge pump output

A low voltage switched-capacitor current reference circuit with low dependence on process, voltage and temperature

Abstract: A low voltage switched-capacitor circuit that generates an almost constant reference current across process, voltage and temperature (PVT) is proposed. The reference voltage is generated by a low voltage band-gap circuit. The output reference current is obtained by applying the generated reference voltage to a low voltage V-I converter. The resistor in the proposed V-I converter is further replaced by a switched capacitor resistor. Due to less variation in the capacitor value across PVT's and high accuracy in integrated voltage reference, the output reference current remains fairly constant. The circuit has been designed in 0.13 /spl mu/m CMOS process at 1.5 V supply voltage. The simulation results show that the output reference current is quite insensitive to PVT and varies linearly with clock frequency and capacitor value of the switched capacitor resistor.

A voltage-balanced phase-shifted three-level DC/DC converter operating from high-input voltage

Abstract: A voltage-balanced phase-shifted three-level DC/DC converter is proposed. Its switch voltage stress is ensured to be only one-half of the input voltage and its four-step operation can reduce considerably the output inductor current ripple. Moreover, it features a small filter, no voltage unbalance problem, static/dynamic sharing of the switch voltage, high-efficiency, and high-power density. It is very suitable for high power converters operating from a high-input voltage.

Intermediate circuit capacitor short-circuit monitoring

Abstract: The invention relates to an electronic circuit for short-circuit monitoring of one of at least two intermediate circuit capacitor units arranged in series, whereby the difference between the voltage at the node point between two of the units for monitoring and a reference voltage derived from the intermediate circuit voltage and relevant to the monitoring, are used as control signal, which, in the case of a capacitor short-circuit, exceeds or falls below a threshold value and an error signal is generated.

Voltage multiplier with charge recovery

Abstract: Capacitive voltage multiplier for generating voltage pulses, preferably up to 100 V, that are higher than the supply voltage for displays, non-volatile memories and corresponding units especially in small electronic devices, such as handheld telecommunication terminals or corresponding devices, wherein the multiplier comprises a switching capacitor circuit ( 21 ) provided with capacitors and switches for charging the capacitors in parallel and discharging them in series in order to deliver a high voltage pulse. The multiplier further comprises a diode chain circuit ( 22 ) consisting of a diode-chain and pumping capacitors for delivering high voltage current. The inventive system allows the output high voltage to be switched on and held with little longtime drop and with small switching losses and able to supply a load current without significant ripple. Additionally switching the high voltage on and off does not result in efficiency loss.

A boosted wordline voltage generator for low-voltage memories

Abstract: A novel voltage tripler using 4 clocks with different phases is present in this work Both the positive and negative polarities of the voltage are generated to serve as the boosted voltage and the back bias voltage The proposed design is carried out by pass transistors and switched capacitors The largest generated voltages which the proposed design can provide is +1109 V and -1062 V given VDD=33 V when the circuit is implemented by TSMC 035 /spl mu/m 1P4M CMOS technology

Self trimming voltage generator

Abstract: Described are integrated circuit chips that are capable of self-adjusting an internal voltage of the integrated circuit chip and methods for adjusting the internal voltage of an integrated circuit chip. The methods include comparing an internally generated voltage to an external target voltage.

Electronic devices and systems

Abstract: A device having a switched impedance that can be switched between a first state and a second state wherein, in the first state, the device acts as a voltage multiplier and, in the second state, the device acts as a rectifier.

Method and apparatus for balancing capacitors in a capacitor bank

Abstract: A method and apparatus are for balancing capacitors in a capacitor bank Three voltage levels are produced by a reference voltage source, to monitor the state of charge of the capacitors The capacitor voltage on each capacitor is determined and is compared with the voltage levels After the charging of the capacitors, normal operation starts when the capacitor voltage reaches the lowest voltage level and before it has reached the central voltage level A balancing operation starts when the capacitor voltages of all the capacitors have reached the central voltage level, and ends when the capacitor voltage of all the capacitors has once again reached the lowest voltage level When the lowest voltage level is reached once again, normal operation starts again A fault is indicated upon reaching the highest voltage level

Induction heating fixing apparatus and image forming apparatus

Abstract: A DC circuit 110 is provided to convert the voltage of a commercial AC power supply 100 into a DC voltage having a fixed level and output the DC voltage irrespective of the level of the voltage. The rectifier circuit 110 includes contacts 117, 118 and 119 and functions as one of a full-wave doubler voltage rectifier circuit and a full-wave rectifier circuit according to the opening and closing of each of the contacts.

Discharge power supply apparatus

Abstract: This discharge power supply apparatus is for supplying a D. C. voltage to a discharge load 6 and discharging the same. The discharge power supply apparatus includes an inverter circuit 2 that converts D. C. voltage to A. C. voltage; a transformer 3 having a primary winding 3 a to which the A. C. voltage output by the inverter circuit 2 is supplied and a secondary winding 3 b ; a full-wave rectifier circuit 4 that has a plurality of diodes 4 A to 4 D and rectifies the A. C. voltage generated by the secondary winding 3 b ; and a trigger capacitor 7 connected in parallel to a part of the diodes of the full-wave rectifier circuit 4.

Voltage divider circuit

Abstract: PROBLEM TO BE SOLVED: To provide a voltage divider circuit that is configured to be capable of outputting a highly accurately divided DC voltage with a comparatively simple structure. SOLUTION: Two semiconductor switches Sd1, Sd2 connected in series and having diodes D1, D2 connected inversely parallel, two semiconductor switches Sd3, Sd4 connected in series and having diodes D3, D4 connected inversely parallel, and voltage divider capacitors Cd1, Cd2 connected so as to divide an output voltage by a desired voltage ratio are connected between upper and lower terminals of a DC voltage source VO. Furthermore, the middle point 'a' of the semiconductor switches Sd1, Sd2 is connected to the middle point 'c' of the voltage divider capacitors Cd1, Cd2 via a voltage limiting element Ld1, and the middle point 'b' of the semiconductor switches Sd3, Sd4 to the middle point 'c' of the voltage divider capacitors Cd1, Cd2 via another voltage limiting element Ld2. The voltage divider circuit is formed by winding inductors, which are the voltage limiting elements Ld1, Ld2, on a common iron core 23. COPYRIGHT: (C)2005,JPO&NCIPI

Integrated charge pump circuit with low power voltage regulation

Abstract: An integrated charge pump circuit providing a regulated output voltage controlled by a voltage regulator with reduced power requirements in which the charge pump output voltage is a substantially constant multiple of the charge pump input voltage as defined by a voltage ratio which, in turn, is defined as a selected combination of a ratio of conductances of circuit elements within a feedback loop and ratios of other voltages including selected reference voltages and the charge pump input voltage.