Denso Corporation

Nippondenso Co., Ltd.

Tomohisa Yamamoto

Hiroyuki Ban

Junji Hayakawa

Satoshi Sobue

Junichi Nagata

Takeshi Ishikawa

Takashi Harada

Masami Kataoka

Masakazu Honda

Katsumi Nakamura

Hiroyuki Ina

Katsuyuki Miyake

Tukasa Miyake

In a combined battery pack of a plurality of battery cells, a comparison circuit compares a voltage appearing at a common connection point between two adjacent battery cells with a reference voltage. Based on a result of the comparison, an electric discharging operation of an electric discharging circuit connected between both terminals of each of the battery cells is carried out. The comparison circuit is driven to operate with a power supply voltage appearing between a positive-side terminal of a battery cell provided on a higher-potential side of a common connection point and the negative-side terminal of the battery cell provided on a lower-potential side of the common connection point.

Cell voltage equalization apparatus for combined battery pack including circuit driven by power supplied by the combined battery pack

A current mirror circuit includes a pair of first and second transistors having bases connected together and emitters connected to a power line, a resistor connected between the bases of the first and second transistors and the power line, a third transistor for providing base currents of the first and second transistors and a resistor current flowing through the resistor, and a current compensation circuit that adds a compensation current to an input current to the first transistor. The amount of the compensation current is approximately equal to that of the resistor current divided by a current gain of the third transistor. Thus, the compensation current compensates the difference between a collector current of the first transistor and the input current.

Current mirror circuit and constant current circuit having the same

A battery ECU controls a main battery composed of a plurality of battery cells connected to each other in series. The battery cells are grouped into cell blocks each having a cell-block monitor circuit. A control unit controls charging/discharging processes on the basis of signals output by the cell-block monitor circuit. A signal output by a cell-block monitor circuit on a high-voltage side turns on a transistor for propagating a signal to a cell-block monitor circuit on a middle-voltage side. In the cell-block monitor circuit on a middle-voltage side, the propagated signal turns on another transistor for further propagating a signal to a cell-block monitor circuit on a low-voltage side. In the cell-block monitor circuit on a low-voltage side, the propagated signal turns on a further transistor for outputting a signal to a control unit.

Circuit system for a battery electronic control unit

In a device having multiple power components adjacently arranged to each other, two diodes are disposed adjacent to each power component. The first diode is placed adjacent to any one of the sides of the power component, and the second diode is placed adjacent to the opposite side of the power component. The sides are opposed to the sides of adjacent power components. An overtemperature detection circuit outputs an overtemperature detection signal when outputs of the diodes both decrease under a reference voltage.

Overtemperature detection device and semiconductor integrated circuit device

A driving circuit having a p-n-p transistor and an n-p-n transistor which are connected in series between a high-voltage side source terminal (V) and a ground terminal, and a plurality of inverters provided on a path through which an input signal is transmitted to both the transistors. One of both the transistors is turned on, and the other is turned off, by means of the inverters to bring an output terminal connected between both the transistors, to any of a high voltage level and a low voltage level. The inverters are each constituted of a bipolar transistor which is element-isolated by silicon oxide layers in an n-silicon layer, and, in addition to inverters each having in the n-silicon layer a psubstrate region for drawing out electric charges, inverters which do not have the psubstrate region are provided in combination with the former.

Driving circuit for push-pull operated transistors

The present invention discloses a charge-pump circuit, which contributes to the improvement of the reliability of capacitor for boosting provided inside even under the condition where supply voltage is changed, and which also contributes to the reduction of consumption current. In this charge-pump circuit, a constant voltage generation circuit generates a reference voltage VS lower by a fixed voltage VT than a supply voltage VB of a power source &plus;B and gives the reference voltage to a booster circuit. The booster circuit comprises an inverter circuit for alternately changing output voltage between the supply voltage VB and the reference voltage VS in response to reverse operation in synchronization with the output of an oscillation circuit, and also an inverter circuit for alternately changing output voltage between the reference voltage VS and the supply voltage VB in response to periodic reverse operation with a phase by 180&deg; different from the phase of said inverter, whereby charging current is supplied via a diode to a first capacitor from the power source &plus;B during the period when output of the inverter circuit is changed to the reference voltage VS, and electric charge charged on the first capacitor is shifted to the second capacitor via the diode during the period when output of the inverter circuit is changed to the reference voltage VS.

Charge-pump circuit and a load-driving circuit utilizing the same

A charge pump circuit comprises a plurality of capacitors arranged to charge and discharge for generating a charged-up voltage. An oscillation circuit generates a clock signal to be applied to the plurality of capacitors to alternately charge and discharge these charge-up capacitors. A monitoring circuit detects electrical potentials on at least two of the charge-up capacitors and controls the clock signal. An oscillating condition of the oscillation circuit based on the electrical potentials on the at least two of the charge-up capacitors.

Charge pump circuit

A current mirror circuit includes an input transistor and an output transistor. A first bipolar transistor has a collector terminal connected to a predetermined reference portion of a current supply path of a power source and an emitter terminal connected to a collector terminal of the output transistor for absorbing an electrical potential difference between the reference portion and the collector terminal of the output transistor. A second bipolar transistor has a base terminal connected to the emitter terminal of the first bipolar transistor and a collector terminal connected to a base terminal of the first bipolar transistor for fixing an electrical potential of the collector terminal of the output transistor to a base-emitter voltage of the second bipolar transistor.

Constant current circuit using a current mirror circuit and its

A diffused resistor capable of suppressing variation of characteristics caused by leakage of current occurring under high-temperature conditions. An N-type layer is epitaxially grown on a P-type substrate, and an N-type resistor island isolated by a P-type isolation region is formed. A P-type diffused resistor is formed in the island. An N-type region of high impurity concentration is disposed in close proximity to the high-potential end of the P-type diffused resistor. An electrode is brought into contact with not only the high-potential end but also the N-type high-impurity concentration region through the same contact hole. Thus, a parasitic transistor, which is formed from the P-type diffused resistor, the N-type resistor island and the P-type substrate (P-type isolation region), can be prevented from turning on with a minimal increase of the element area.

Semiconductor diffused resistor

A driving circuit of a pulse motor for use in a vehicle odometer is provided. The driving circuit includes a pulse source for providing drive pulses, in sequence, to a plurality of phase coils of the pulse motor, and a wave-shaper for shaping leading and trailing edges of each of the drive pulses so as to vary at a given rate in plural steps for noiseless smooth rotation of the pulse motor.

Pulse motor driver

A pulse signal generated by a car speed sensor is converted to an analog voltage by a F-V converter, and two sawtooth signals are formed by two sawtooth current generators based on the analog voltage. The sawtooth currents are then converted into two triangular wave voltages by two I-V converters. Three-stage function generators change the slope of each of the triangular wave voltages step by step and form an approximated sine wave voltage and an approximated cosine wave voltage. A zero-cross compensating circuit is provided in each of the first stage function generators and adjust the triangular voltage to cross zero point.

Driving apparatus for cross-coil type analog indicating instrument

An input signal processing apparatus for use in a comparator which compares an input signal with a reference voltage signal to output a signal inverted in accordance with a comparison result. The apparatus detects the frequency of an input signal from a rotation detecting device such as pickup coil so that a mask time is set in accordance with the detected input signal frequency. The apparatus separates the levels of the input signal and a reference signal to the comparator for the mask time. The mask time is set so as to vary with a first predetermined rate of change when the input signal frequency is below a predetermined frequency and vary with a second predetermined rate of change greater than the first predetermined rate of change when the input signal frequency is above the predetermined frequency. This arrangement can appropriately set the mask time whereby it is possible to prevent the phase shift in waveshaping when the frequency of the input signal is high.

Wave-shaping apparatus

A driving apparatus used for an analog indicating instrument having a pair of cross coils comprises a pulse signal generating device for generating a pulse signal having a frequency proportional to a quantity to be measured, a frequency-voltage conversion device for generating a ripple voltage proportional to the frequency of the pulse, holding a mean voltage of the ripple voltage as an analog voltage while restraining the ripple, and controlling the analog voltage so as to change following a mean value of the ripple voltage, thereby to supply the analog voltage, and driving devices for supplying a current in accordance with the analog voltage to the cross coils so as to drive these cross coils. The driving apparatus has effects on improving responsibility of frequency-voltage conversion operation in a low frequency region and reducing the deflection of a pointer of an instrument by restraining the ripples.

An apparatus for driving a gauge having coils in quadrature to generate a resultant magnetic field in accordance with currents applied thereto and having a pointer angularly swept by the field, the apparatus having a memory to store a first data defining a relationship between a first level, indicative of the current applied to one of the coils, and an angle of the pointer. The first level has a continous waveform varying in isoceles trapezoid form over an angle range of 0.degree. to 180.degree.. The first data varies symmetrically with the isoceles trapezoid wave at the 180.degree. pointer angle over an angle range of 180.degree. to 360.degree.. The memory is arranged to store second data defining a relationship between a second level indicative of the current applied to the other coil and the pointer angle. The second level has a continuous waveform phase shifted by 90.degree. from the continuous waveform of the first data. The apparatus also has an output generator to generate output signals indicative of first and second levels related to the first and second data. A driving circuit is responsive to the output signals to drive the coils with currents proportional to the first and second levels. Each continuous waveform of the first and second data is modified so as to be cut triangularly at its corner portions.

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Hoi-gun, Japan

Tomohisa Yamamoto