Abstract: Provided is a controller circuit of a buck DC/DC converter. The controller circuit includes a feedback pin to be connected to an output line of the buck DC/DC converter, a voltage divider circuit including a first resistor and a second resistor connected in series between the feedback pin and a ground, a feedback circuit that generates a pulse modulation signal to bring a feedback voltage as an output of the voltage divider circuit close to a reference voltage, and a current source that is connected to the feedback pin and supplies a constant current.

Abstract: A semiconductor integrated circuit includes multiple termination circuits that correspond to multiple target pins. The multiple termination circuits each include a first resistor and a first transistor coupled in series between the corresponding target pin and the ground. A second resistor is provided between the corresponding target pin and the control electrode of the first transistor. The enable circuit is arranged such that its output node is coupled to the control electrode of the first transistor, and configured such that (i) when the enable pin is set to the first state, the current is sunk from the output node, and (ii) when the enable pin is set to the second state, the output node is set to the low level.

Abstract: A semiconductor integrated circuit includes multiple termination circuits that correspond to multiple target pins. The multiple termination circuits each include a first resistor and a first transistor coupled in series between the corresponding target pin and the ground. A second resistor is provided between the corresponding target pin and the control electrode of the first transistor. The enable circuit is arranged such that its output node is coupled to the control electrode of the first transistor, and configured such that (i) when the enable pin is set to the first state, the current is sunk from the output node, and (ii) when the enable pin is set to the second state, the output node is set to the low level.

Abstract: A pulse generator includes a mode controller that detects a state in which there has been no transition of a pulse signal to the off level for a given cycle (period). When such a state is detected, the pulse generator transits to a skip mode. In the skip mode, the period is repeatedly switched between: (i) a first period in which the pulse signal is maintained at the on level over multiple cycles; and (ii) a second period in which the pulse signal is forcibly switched to the off level so as to charge the bootstrap capacitor by means of a bootstrap circuit.

Abstract: A bootstrap power supply circuit generates a constant voltage VCCBST for charging a bootstrap capacitor. An output transistor is configured as an N-channel MOSFET arranged such that its drain is connected to an input line and such that its source is connected to an output line. A constant voltage circuit connected to the gate of the output transistor stabilizes the gate voltage VG to a constant value. A variable impedance circuit is arranged between the input line and the gate of the output transistor, in order to provide a variable impedance. An impedance controller controls the impedance of the variable impedance circuit according to the state of a step-down DC/DC converter.

Abstract: A pulse generator includes a mode controller that detects a state in which there has been no transition of a pulse signal to the off level for a given cycle (period). When such a state is detected, the pulse generator transits to a skip mode. In the skip mode, the period is repeatedly switched between: (i) a first period in which the pulse signal is maintained at the on level over multiple cycles; and (ii) a second period in which the pulse signal is forcibly switched to the off level so as to charge the bootstrap capacitor by means of a bootstrap circuit.

Abstract: A bootstrap power supply circuit generates a constant voltage VCCBST for charging a bootstrap capacitor. An output transistor is configured as an N-channel MOSFET arranged such that its drain is connected to an input line and such that its source is connected to an output line. A constant voltage circuit connected to the gate of the output transistor stabilizes the gate voltage VG to a constant value. A variable impedance circuit is arranged between the input line and the gate of the output transistor, in order to provide a variable impedance. An impedance controller controls the impedance of the variable impedance circuit according to the state of a step-down DC/DC converter.

Abstract: A shunt circuit includes: a shunt resistor; a transistor connected in parallel to a storage element via the shunt resistor; a first OP amplifier configured to compare a battery voltage supplied to the storage element with a detection voltage; and a second OP amplifier configured to shunt a shunt current from a charging current supplied from a charging unit when the battery voltage reaches the detection voltage. The detection voltage is increased step by step, and the shunt current is increased whenever the battery voltage reaches the detection voltage.

Abstract: An electrical storage device monitoring circuit includes a 3-state buffer configured to switch between a high output state and a low output state based on a flag output delivered from a previous electrical storage device monitoring circuit at a front stage, and also configured to detect a disconnection between the current electrical storage device monitoring circuit and the previous electrical storage device monitoring circuit at the front stage; a detection circuit configured to monitor an electrical storage device to detect whether the electrical storage device is normal or abnormal; and an output circuit configured to deliver the flag output to a subsequent electrical storage device monitoring circuit at a next stage based on an input of the 3-state buffer and a detection result of the detection circuit.

Abstract: An energy harvesting apparatus includes: a capacitor configured to store energy generated by an energy harvesting element; and a switch connected to the capacitor and configured to switch energy supply from the capacitor to a load based on a capacitor voltage with which the capacitor is charged. An energy harvesting system includes: energy harvesting elements; energy harvesting apparatuses which are provided to respectively correspond to the energy harvesting elements; and a load as an energy supply destination connected to the energy harvesting apparatuses.

Abstract: A battery module includes an anode terminal, a cathode terminal, and multiple capacitor cells. Multiple tap electrodes are each provided to a corresponding connection node that connects adjacent capacitor cells. An intermediate terminal is connected to one from among the multiple tap electrodes. A battery control circuit includes a cell balance circuit configured to stabilize each of the voltages at the multiple tap electrodes to a corresponding target voltage level. The voltage at the anode terminal is supplied to the power supply terminal of the cell balance circuit.

Abstract: An electrical storage device monitoring circuit includes a 3-state buffer configured to switch between a high output state and a low output state based on a flag output delivered from a previous electrical storage device monitoring circuit at a front stage, and also configured to detect a disconnection between the current electrical storage device monitoring circuit and the previous electrical storage device monitoring circuit at the front stage; a detection circuit configured to monitor an electrical storage device to detect whether the electrical storage device is normal or abnormal; and an output circuit configured to deliver the flag output to a subsequent electrical storage device monitoring circuit at a next stage based on an input of the 3-state buffer and a detection result of the detection circuit.

Abstract: An energy harvesting apparatus includes: a capacitor configured to store energy generated by an energy harvesting element; and a switch connected to the capacitor and configured to switch energy supply from the capacitor to a load based on a capacitor voltage with which the capacitor is charged. An energy harvesting system includes: energy harvesting elements; energy harvesting apparatuses which are provided to respectively correspond to the energy harvesting elements; and a load as an energy supply destination connected to the energy harvesting apparatuses.

Abstract: A shunt circuit includes: a shunt resistor; a transistor connected in parallel to a storage element via the shunt resistor; a first OP amplifier configured to compare a battery voltage supplied to the storage element with a detection voltage; and a second OP amplifier configured to shunt a shunt current from a charging current supplied from a charging unit when the battery voltage reaches the detection voltage. The detection voltage is increased step by step, and the shunt current is increased whenever the battery voltage reaches the detection voltage.

Abstract: A battery module includes an anode terminal, a cathode terminal, and multiple capacitor cells. Multiple tap electrodes are each provided to a corresponding connection node that connects adjacent capacitor cells. An intermediate terminal is connected to one from among the multiple tap electrodes. A battery control circuit includes a cell balance circuit configured to stabilize each of the voltages at the multiple tap electrodes to a corresponding target voltage level. The voltage at the anode terminal is supplied to the power supply terminal of the cell balance circuit.

Abstract: A first switch is arranged between a judgment unit and a signal line. The first switch is turned on during a period in which the judgment unit judges a device, after which the first switch is turned off. A second switch is turned off during a period in which the judgment unit judges the device, after which the second switch is turned on. The signal line connects a communication interface port, which allows various different kinds of devices to be connected, and a communication terminal of a processor configured to perform data communication with the device. The judgment unit monitors the electrical state of the signal line, and judges the device connected to the port.

Abstract: A voltage comparison circuit makes a comparison between a first voltage and a second voltage. A resistor and a constant current source are provided in series between the first voltage and the ground voltage. A comparator receives the second voltage via one input terminal (non-inverting input terminal), and the voltage at a connection node between the aforementioned resistor and the constant current source via the other input terminal (inverting terminal). The first voltage is preferably used as the power supply voltage for the comparator.

Abstract: An external power source is connected to an adapter input terminal (first terminal). A battery is connected to a path input terminal (second terminal). A selection circuit (a first switch, a second switch, logic circuit compares the input voltage input from the external power supply with the battery voltage, and selects one of the two. The voltage thus selected by the selection circuit is output to an external load circuit via a system power supply terminal. A charging circuit charges the battery using the input voltage supplied from the external power supply.

Abstract: A first switch is arranged between a judgment unit and a signal line. The first switch is turned on during a period in which the judgment unit judges a device, after which the first switch is turned off. A second switch is turned off during a period in which the judgment unit judges the device, after which the second switch is turned on. The signal line connects a communication interface port, which allows various different kinds of devices to be connected, and a communication terminal of a processor configured to perform data communication with the device. The judgment unit monitors the electrical state of the signal line, and judges the device connected to the port.

Abstract: An external power source is connected to an adapter input terminal (first terminal). A battery is connected to a path input terminal (second terminal). A selection circuit (a first switch, a second switch, a logic circuit compares the input voltage input from the external power supply with the battery voltage, and selects one of the two. The voltage thus selected by the selection circuit is output to an external load circuit via a system power supply terminal. A charging circuit charges the battery using the input voltage supplied from the external power supply.