Provided are a battery state monitoring circuit and a battery device which are capable of inhibiting discharge without enabling an overdischarge cell balance function when an overcurrent detection circuit detects a discharge overcurrent, without the need for an additional terminal of the battery state monitoring circuit. A detection signal of the overcurrent detection circuit is input to each of a communication terminal for overdischarge signal and a communication terminal for overcharge signal included in the battery state monitoring circuit provided on a side of the overcurrent detection circuit. An overdischarge cell balance circuit outputs a cell balance signal when an overdischarge detection signal indicates an overdischarge non-detected state, an overdischarge signal indicates an overdischarge detected state, and an overcharge signal indicates an overcharge non-detected state.

Battery state monitoring circuit and battery device

Provided is a battery device for controlling charge/discharge of a secondary battery by a single bidirectionally conductive field effect transistor, a charge/discharge control circuit with which a leakage current of the bidirectionally conductive field effect transistor is reduced to perform stable operation. The charge/discharge control circuit includes: a switch circuit for controlling a gate of the bidirectionally conductive field effect transistor based on an output of a control circuit for controlling the charge/discharge of the secondary battery; and two MOS transistors for preventing back-flow of a charge current and a discharge current. The first MOS transistor has a drain and a back gate which are connected to each other, and a source connected to a drain of the bidirectionally conductive field effect transistor. The second MOS transistor has a drain and a back gate which are connected to each other, and a source connected to a source of the bidirectionally conductive field effect transistor.

Charge and discharge control circuit and battery device

A regulator includes a transistor connected between an input and an output. A feedback voltage controls the transistor to keep the output voltage constant. A first circuit functions as a comparator to compare a detection voltage from the output of the transistor and the feedback voltage when the output current is higher than a predetermined value, and functions as a buffer when the output current is lower than the predetermined value. A second circuit receives a reference voltage, the feedback voltage, and an output from the first circuit, and generates (i) a difference between the feedback voltage and the first circuit output when the reference voltage is lower than the first circuit output, and (ii) a difference voltage between the feedback voltage and the reference voltage when the reference voltage is higher than the first circuit output, and supplies a control voltage to control the output of the transistor.

Semiconductor integrated circuit for regulator

Provided is a charging and discharging protection circuit realizing low current consumption in an overcurrent detection state, easy calculation of an automatic return impedance, and high usability. A pull-down circuit for pulling down an overcurrent detection terminal to a VSS terminal is connected in series between the overcurrent detection terminal and a switching circuit. The switching circuit is connected in series between the pull-down circuit and the VSS terminal.

Charging and discharging control circuit and charging type power supply device

A reference voltage circuit having a high power supply rejection ratio, and can operate at low voltage is provided. The reference voltage circuit includes a bias circuit constructed such that a depletion type transistor ( 3 ) is connected in series to a power supply voltage supply terminal of a load circuit, an enhancement type MOS transistor ( 4 ) for detecting current through the load circuit to operate as a current source is connected to the load circuit, a depletion type MOS transistor ( 5 ) is connected in series to the transistor ( 4 ), and a gate terminal of the transistor ( 5 ) is connected to a source terminal of the transistor ( 5 ), in which the gate terminal of the depletion type transistor ( 3 ) is connected to the source terminal of the depletion type transistor ( 5 ).

Cascode circuit and semiconductor device

PROBLEM TO BE SOLVED: To provide a power supply integrated circuit including an overheat protection circuit with a high detection accuracy. SOLUTION: The overheat protection circuit includes a current generation circuit which is provided with a first metal oxide semiconductor (MOS) transistor whose gate and drain terminals are connected to each other and which operates in a weak inversion region; a second MOS transistor whose gate terminal is connected to that of the first MOS transistor and which has a conductivity type identical to that of the first MOS transistor and operates in a weak inversion region; and a first resistive element connected to the source terminal of the second MOS transistor, and a comparator which compares the reference voltage having positive temperature characteristics with a temperature voltage having negative temperature characteristics, both of which are obtained based on a current generated by the current generation circuit. COPYRIGHT: (C)2011,JPO&INPIT

Overheat protection circuit and power supply for an integrated circuit

PROBLEM TO BE SOLVED: To provide a charging/discharging control circuit for preventing flow of a charging current into a secondary battery via a resistor and a parasitic diode for recovery from an overcurrent, even when a switch circuit is OFF. SOLUTION: Flow of a charging current through the parasitic diode 202 is stopped, even when the switch circuit 102 is OFF and a charger 104 is connected by detecting connection of the charger 104 and separating a resistor 123 from an overcurrent detecting terminal. COPYRIGHT: (C)2002,JPO

Charging/discharging control circuit and chargeable power supply

PROBLEM TO BE SOLVED: To provide a charging and discharging control circuit that has shortened the testing time for overcharge detecting voltage and an overdischarge detecting voltage. SOLUTION: A charging and discharging control circuit is formed which is shifted to a test mode to shorten the delay time of the internal control circuit, when a voltage higher than the prescribed value is applied to the charger connecting terminal of a charging power source device.

Charging and discharging control circuit and charging power source device

PURPOSE: To obtain a charging/discharging control circuit in which unbalanced consumption of the secondary batteries is prevented by connecting a buffer having very high impedance with a terminal for detecting the terminal potential of a plurality of secondary batteries connected in series thereby equalizing the currents being fed to respective secondary batteries. CONSTITUTION: The charging/discharging control circuit is connected, at the outer terminal -VO or +VO thereof, with a plurality of secondary batteries 101, 102 through a switch circuit 103. The terminal for detecting the potential between the plurality of secondary batteries is connected with a buffer 110 which is fed with power through the terminals -VO and VO. The buffer 110 outputs the potential between secondary batteries to the joint of a plurality of voltage divider circuits 104, 105. When the buffer 110 is constituted of an MOSFET, a substantially infinite input impedance can be obtained because the gate-drain impedance and the gate-source impedance are infinite, and thereby no current flow into the input terminal. COPYRIGHT: (C)1996,JPO

Charging/discharging control circuit

PROBLEM TO BE SOLVED: To provide a reference voltage circuit that decreases difference in voltages added to the reference voltage circuit thereby reduce the difference of each output voltage. SOLUTION: Depletion MOS transistors 3, 6 are connected in series to drains of depletion MOS transistors 1, 4 in two ED type reference voltage circuits, respectively. Gates of the serially connected depletion MOS transistors 3, 6 are connected to each other's source. Consequently, the difference of voltages added to each ED type reference voltage circuit is reduced, thereby reducing the difference of each output voltage. COPYRIGHT: (C)2004,JPO

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Papers

Overheat protection circuit and power supply for an integrated circuit

Charging/discharging control circuit and chargeable power supply

Charging and discharging control circuit and charging power source device

Charging/discharging control circuit

Reference voltage circuit and electronic apparatus

貴雄 中下

Papers

Overheat protection circuit and power supply for an integrated circuit

Charging/discharging control circuit and chargeable power supply

Charging and discharging control circuit and charging power source device

Charging/discharging control circuit

Reference voltage circuit and electronic apparatus

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