Abstract: A constant voltage power supply circuit is provided with a constant voltage circuit part to convert an input voltage into a predetermined constant voltage, a first excessive current protection circuit part to control the constant voltage circuit part so as to reduce the output voltage while maintaining an output current that is output to a predetermined maximum value if the output current is greater than or equal to the predetermined maximum value when the output voltage is a rated voltage, and a second excessive current protection circuit part to control the constant voltage circuit part so as to reduce the output voltage and the output current and to output a short-circuit current if the output voltage decreases to a ground voltage when the output voltage is decreased to a predetermined value by the first excessive current protection circuit part. The second excessive current protection circuit part is disabled in response to a first test signal that is active.

Abstract: A constant voltage circuit is disclosed that includes a constant voltage generator circuit part converting an input voltage into a predetermined constant voltage in accordance with an externally input control signal and outputting the constant voltage; a first capacitor connected to the output end of the constant voltage generator circuit part; a second capacitor charging the first capacitor; and a switch circuit part controlling charging and discharging of the second capacitor in accordance with the control signal. The switch circuit part charges the second capacitor and blocks the discharging of the second capacitor to the first capacitor when the constant voltage generator circuit part is caused to stop outputting the constant voltage by the control signal, and stops applying the input voltage to the second capacitor and charges the first capacitor when the constant voltage generator circuit part is caused to start outputting the constant voltage by the control signal.

Abstract: A constant-voltage circuit includes a first transistor, a first control circuit, and a second control circuit having a second transistor and a differential amplifier. The first transistor controls an output current according to a first control signal output by the first control circuit such that an output voltage is substantially equal to a predetermined voltage. The second control circuit has a response property faster than the first control circuit to a variation of the output voltage, and causes the first transistor to increase the output current for a predetermined time period, regardless of the first control signal, when the output voltage varied to an extent greater than a predetermined output voltage variation value. The second transistor controls an operation of the first transistor according to a second control signal output by the differential amplifier such that a voltage at an inverting input terminal is substantially equal to the bias voltage.

Abstract: A charge pump circuit is provided for generating a voltage (1+1/n) times as high as a supply voltage. The charge pump circuit eliminates the need for diodes for preventing a current from flowing back from a high potential side of capacitors to prevent a reduction in the voltage due to a forward voltage, and reduces a reactive current and latch-up when the charge pump circuit is integrated into a single IC chip. The charge pump circuit includes a fourth switching element having a substrate gate connected to a drain for preventing a current from flowing back to an input terminal from a high potential side of fly back capacitors connected in series, and a second switching element having a substrate gate connected to a drain for preventing a current from flowing back from a high potential side of a catch-up capacitor to the fly back capacitors connected in series.

Abstract: A constant-voltage power circuit incorporating an over-current protection circuit having a fold back current limiting capability operative through low input voltages, and being capable of arbitrarily setting current outputs. The constant-voltage power supply circuit is configured so that a voltage output with small amplitude from a differential amplifier circuit is subjected to amplitude expansion to be amplified to range fully from the ground potential approximately to the input voltage by means of an amplitude expansion circuit, which includes an inverter consisting of an NMOS transistor and a resistor, and that the voltage resulting from the amplitude expansion is subsequently input to the gate of a PMOS transistor configured to directly control an output transistor.

Abstract: A constant voltage circuit is disclosed that includes a constant voltage generator circuit part converting an input voltage into a predetermined constant voltage in accordance with an externally input control signal and outputting the constant voltage; a first capacitor connected to the output end of the constant voltage generator circuit part; a second capacitor charging the first capacitor; and a switch circuit part controlling charging and discharging of the second capacitor in accordance with the control signal. The switch circuit part charges the second capacitor and blocks the discharging of the second capacitor to the first capacitor when the constant voltage generator circuit part is caused to stop outputting the constant voltage by the control signal, and stops applying the input voltage to the second capacitor and charges the first capacitor when the constant voltage generator circuit part is caused to start outputting the constant voltage by the control signal.

Abstract: A constant-voltage circuit includes a first transistor, a first control circuit, and a second control circuit having a second transistor and a differential amplifier. The first transistor controls an output current according to a first control signal output by the first control circuit such that an output voltage is substantially equal to a predetermined voltage. The second control circuit has a response property faster than the first control circuit to a variation of the output voltage, and causes the first transistor to increase the output current for a predetermined time period, regardless of the first control signal, when the output voltage varied to an extent greater than a predetermined output voltage variation value. The second transistor controls an operation of the first transistor according to a second control signal output by the differential amplifier such that a voltage at an inverting input terminal is substantially equal to the bias voltage.

Abstract: A constant-voltage power circuit incorporating an over-current protection circuit having a fold back current limiting capability operative through low input voltages, and being capable of arbitrarily setting current outputs. The constant-voltage power supply circuit is configured so that a voltage output with small amplitude from a differential amplifier circuit is subjected to amplitude expansion to be amplified to range fully from the ground potential approximately to the input voltage by means of an amplitude expansion circuit, which includes an inverter consisting of an NMOS transistor and a resistor, and that the voltage resulting from the amplitude expansion is subsequently input to the gate of a PMOS transistor configured to directly control an output transistor.

Abstract: A constant voltage outputting apparatus includes a differential amplifier circuit, an amplifier circuit, a current adjustment device and a stabilization circuit. The differential amplifier circuit performs a differential amplifying operation and outputs a differential amplified voltage. The amplifier circuit amplifies the differential amplified voltage output from the differential amplifier circuit. The current adjustment device adjusts a current characteristic of the amplifier circuit. The stabilization circuit stabilizes a state of the current adjustment device. A constant voltage outputting method is also described.

Abstract: A constant voltage circuit including an input terminal to receive an input voltage, an output terminal configured to output a constant voltage converted from the input voltage to a load and an overcurrent protection circuit portion to perform an overcurrent protection operation of restricting an output current from the output terminal within a threshold current and to generate and provide logic signals including information on an operation state of the overcurrent protection operation to a control device disposed outside the constant voltage circuit to control the load based on the information.

Abstract: A constant voltage power supply for supplying power to a load that switches between an active state and a standby state is disclosed. The constant voltage power supply includes first and second constant voltage circuits different in transient response and current consumption. The input of each of the first and second constant voltage circuits is connected to the input terminal of the constant voltage power supply, and the output of each of the first and second constant voltage circuits is connected to the output terminal of the constant voltage power supply. A switching signal generation circuit outputs a switching signal so as to cause the first operational amplifier to operate when the load is in the active state, and to cause the second operational amplifier to operate when the load is in the standby state.

Abstract: A constant-voltage power circuit incorporating an over-current protection circuit having a fold back current limiting capability operative through low input voltages, and being capable of arbitrarily setting current outputs. The constant-voltage power supply circuit is configured so that a voltage output with small amplitude from a differential amplifier circuit is subjected to amplitude expansion to be amplified to range fully from the ground potential approximately to the input voltage by means of an amplitude expansion circuit, which includes an inverter consisting of an NMOS transistor and a resistor, and that the voltage resulting from the amplitude expansion is subsequently input to the gate of a PMOS transistor configured to directly control an output transistor.

Abstract: A constant voltage power supply circuit is provided with a constant voltage circuit part to convert an input voltage into a predetermined constant voltage, a first excessive current protection circuit part to control the constant voltage circuit part so as to reduce the output voltage while maintaining an output current that is output to a predetermined maximum value if the output current is greater than or equal to the predetermined maximum value when the output voltage is a rated voltage, and a second excessive current protection circuit part to control the constant voltage circuit part so as to reduce the output voltage and the output current and to output a short-circuit current if the output voltage decreases to a ground voltage when the output voltage is decreased to a predetermined value by the first excessive current protection circuit part. The second excessive current protection circuit part is disabled in response to a first test signal that is active.

Abstract: A resistance hybrid is disclosed including m+1 unit resistors connected in series, to further be connected in series between two resistance elements, one Rbottom and the other Rtop. Each unit resistor SBn includes an error correction resistance element Rldn and a set resistance element RTn connected in series, and further connected in parallel to a fuse RLn. In addition, the error correction resistance element Rldn is formed such that the combined resistance of the fuse RLn, set resistance element RTn, and error correction resistance element Rldn, is equal to the resistance value of the error correction resistance element Rldn. The value of resistance of the unit resistor SBn after the disconnection increases by the resistance value of set resistance element RTn, to thereby obviating the error possibly caused by the disconnection, which is originated from the resistance value of the fuse RLn.

Abstract: A charge pump circuit is provided for generating a voltage (1+1/n) times as high as a supply voltage. The charge pump circuit eliminates the need for diodes for preventing a current from flowing back from a high potential side of capacitors to prevent a reduction in the voltage due to a forward voltage, and reduces a reactive current and latch-up when the charge pump circuit is integrated into a single IC chip. The charge pump circuit includes a fourth switching element having a substrate gate connected to a drain for preventing a current from flowing back to an input terminal from a high potential side of fly back capacitors connected in series, and a second switching element having a substrate gate connected to a drain for preventing a current from flowing back from a high potential side of a catch-up capacitor to the fly back capacitors connected in series.

Abstract: A constant-voltage circuit includes a first transistor, a first control circuit, and a second control circuit having a second transistor and a differential amplifier. The first transistor controls an output current according to a first control signal output by the first control circuit such that an output voltage is substantially equal to a predetermined voltage. The second control circuit has a response property faster than the first control circuit to a variation of the output voltage, and causes the first transistor to increase the output current for a predetermined time period, regardless of the first control signal, when the output voltage varied to an extent greater than a predetermined output voltage variation value. The second transistor controls an operation of the first transistor according to a second control signal output by the differential amplifier such that a voltage at an inverting input terminal is substantially equal to the bias voltage.

Abstract: A resistance hybrid is disclosed including m+1 unit resistors connected in series, to further be connected in series between two resistance elements, one Rbottom and the other Rtop. Each unit resistor SBn includes an error correction resistance element R1dn and a set resistance element RTn connected in series, and further connected in parallel to a fuse RLn. In addition, the error correction resistance element R1dn is formed such that the combined resistance of the fuse RLn, set resistance element RTn, and error correction resistance element R1dn, is equal to the resistance value of the error correction resistance element R1dn. The value of resistance of the unit resistor SBn after the disconnection increases by the resistance value of set resistance element RTn, to thereby obviating the error possibly caused by the disconnection, which is originated from the resistance value of the fuse RLn.

Abstract: A charge pump circuit is provided for generating a voltage (1+1/n) times as high as a supply voltage. The charge pump circuit eliminates the need for diodes for preventing a current from flowing back from a high potential side of capacitors to prevent a reduction in the voltage due to a forward voltage, and reduces a reactive current and latch-up when the charge pump circuit is integrated into a single IC chip. The charge pump circuit includes a fourth switching element having a substrate gate connected to a drain for preventing a current from flowing back to an input terminal from a high potential side of fly back capacitors connected in series, and a second switching element having a substrate gate connected to a drain for preventing a current from flowing back from a high potential side of a catch-up capacitor to the fly back capacitors connected in series.

Abstract: A constant-voltage circuit uses a capacitor having a low ESR (equivalent serial resistance), such as a ceramic capacitor, for phase compensation, wherein a voltage drop of an output voltage due to a resistance provided for optimizing the phase compensation is compensated for by providing output current to an output a current proportional to an voltage detecting resistance through a current mirror circuit thereby the voltage drop of the output voltage is compensated for.

Abstract: A constant voltage circuit is disclosed that includes a constant voltage generator circuit part converting an input voltage into a predetermined constant voltage in accordance with an externally input control signal and outputting the constant voltage; a first capacitor connected to the output end of the constant voltage generator circuit part; a second capacitor charging the first capacitor; and a switch circuit part controlling charging and discharging of the second capacitor in accordance with the control signal. The switch circuit part charges the second capacitor and blocks the discharging of the second capacitor to the first capacitor when the constant voltage generator circuit part is caused to stop outputting the constant voltage by the control signal, and stops applying the input voltage to the second capacitor and charges the first capacitor when the constant voltage generator circuit part is caused to start outputting the constant voltage by the control signal.