Abstract: Provided is a switching regulator which is capable of reducing soft start time when being activated, and prolonging battery life. The switching regulator has a configuration in which a clamp circuit for clamping a reference voltage is provided in a soft start circuit, and a predetermined period of time since the switching regulator has been activated is divided into a plurality of segments to increase the reference voltage with different slopes for each of the plurality of segments. At an early stage of the activation, the reference voltage is set to be low for preventing an inrush current from a power source, and thereafter, a rate of increase in reference voltage is gradually increased, to thereby reduce the soft start time.

Abstract: Provided is a voltage divider circuit for dividing an input voltage in accordance with a predetermined ratio with high accuracy, in which a source current does not flow from a voltage source and a sink current does not flow into the voltage source.

Abstract: Provided is a switching regulator which is capable of reducing soft start time when being activated, and prolonging battery life. The switching regulator has a configuration in which a clamp circuit for clamping a reference voltage is provided in a soft start circuit, and a predetermined period of time since the switching regulator has been activated is divided into a plurality of segments to increase the reference voltage with different slopes for each of the plurality of segments. At an early stage of the activation, the reference voltage is set to be low for preventing an inrush current from a power source, and thereafter, a rate of increase in reference voltage is gradually increased, to thereby reduce the soft start time.

Abstract: Provided is a voltage divider circuit for dividing an input voltage in accordance with a predetermined ratio with high accuracy, in which a source current does not flow from a voltage source and a sink current does not flow into the voltage source.

Abstract: An improved charge pump circuit includes one switch element driven by a ramp waveform to precisely control the output voltage. The circuit includes a switch group having one or more switch elements for transferring a charge to one or more capacitors, a feedback circuit having an error amplifier for amplifying a difference between a divided output voltage and a reference voltage, a compensation circuit for phase compensating the feedback network, an oscillator for generating the ramp waveform, and a control circuit for driving the one or more switch elements. At least one of the switch elements has a resistance that can be adjusted externally and is driven by the ramp waveform such that its resistance varies with time. Accordingly, the charge transferred from a power source to the one or more capacitors can easily be adjusted. When the charge transferred is small, the on-time of the ramp waveform is short and the average value of the resistance is large.

Abstract: In an electronic circuit having a voltage supply means, a load means, and a regulating means, in order to limit the current flowing through a load, a supply voltage/current regulator is provided which comprises a voltage dividing circuit for dividing the supply voltage of a voltage supply, a reference voltage generator for generating a reference voltage, and a differential amplifier for comparing the divider output voltage and the reference voltage and for producing an output signal in accordance with the difference. The output signal is provided to the base of a transistor connected between the voltage supply and the load. The transistor is effective limit the current flow through the load such that the supply voltage does not decrease below a predetermined limit. By limiting the flow of current through the load such that the supply voltage does not decrease below a predetermined limit, the load may be driven continuously without the problem of lock-up common in ordinary voltage regulators.

Abstract: A switching transistor is arranged for charging a capacitor in response to a positive going transition of a clock signal. The charging time of the capacitor is determined by controlling the charging current in accordance with an input voltage to a transistor coupled to the capacitor. The pulse width of an output signal is dependent upon the charging time of the capacitor. Using the inventive pulse width modulator, by comparing the voltage of a reference voltage source with a divided voltage obtained through feedback of the output of the pulse width modulator, a switching power source is obtained by simply adding circuitry for converting, rectifying and smoothing the output voltage. A variable range of pulse width of up to 1800 times can be obtained. When the circuit is designed using complementary MOS devices, the operating voltage can be under 1V with a consumption current of less than several .mu.A.