|
The present invention provides a current comparator that reduces both input and output resistance. The current comparator positions a resistive feedback network in a first inverting amplifier of an input stage. The input stage according to the present invention can include a first and a second input terminal, an output terminal, a reference current source, a load circuit, a driving unit, and a resistive circuit. The reference current source supplies a reference current to the first input termina...
When a circuit is activated, bases of transistors Q1 and Q2 making up a first current mirror circuit 7 are grounded through switch means 10, whereby a current is forcibly made to flow into the bases of the transistors Q1 and Q2. Thus, the circuit operation can be made reliable at the activation time. A part of load current is shunted with good accuracy via a resistor R1 having a first resistance value of a predetermined magnification of a resistance value of a shunt resistor Rs, the first curren...
A current limiter used for stable control of an electric power system, and particularly applied to a high voltage of the electric power system, has a reduced voltage for suppressing the overcurrent of the electric power system. The current limiter is not enlarged so that the current limiter secures the insulation of the voltage withstanding level, and the current limiter is easy to be introduced to the system. A limiting device is inserted between a low potential terminal of a winding of a star-...
A current protector comprising an organic resin-made insulating substrate, a pair of terminals formed at both ends of the insulating substrate, and an electrical conductor electrically connecting the terminals and having a thickness of 3-8 .mu.m and formed in or on the insulating substrate, is excellent in suppressing ignition and smoking at the time of blowing, and can be improved in clearing characteristics by various modifications.
A current amplifier includes a cascode transistor for fixing the voltage of an input of the amplifier; a first constant current source connected between the input and a first supply voltage; a second constant current source, for providing a current lower than the first current source, connected between a second supply voltage and the cascode transistor; a second transistor, of different type than the cascode transistor, connected between the input and the second supply voltage, and controlled by...
A current transformer for mains alternating current with dc components is formed of at least one transformer core with a primary winding and at least one secondary winding, of load resistor is connected in parallel to the secondary winding and terminates the secondary circuit in low-impedance fashion. A semiconductor component that opens during a suitable time span within every cycle and is in turn closed is provided in the secondary circuit. During this time span, the secondary circuit is in a ...
A current limiter used for stable control of an electric power system, and particularly applied to a high voltage of the electric power system, has a reduced voltage for suppressing the overcurrent of the electric power system. The current limiter is not enlarged so that the current limiter secures the insulation of the voltage withstanding level, and the current limiter is easy to be introduced to the system. A limiting device is inserted between a low potential terminal of a winding of a star-...
A method and circuit for producing an output current is provided. The method and circuit adds two currents with opposing temperature coefficients to produce such output current. A first one of the two currents, I.sub.1, is a scaled copy of current produced in a temperature compensated bandgap reference circuit. A second one of the two currents, I.sub.2, is derived from a temperature stable voltage produced by the bandgap circuit divided by a positive temperature coefficient resistance. The added...
A current limiter is provided that includes a power switch for receiving input power from a power source and passing at least a portion of the input power to an output, a current sense mechanism coupled to the power switch for sensing current flowing through the current limiter and for providing a current flow signal related to the current flow through the current limiter, and a control mechanism coupled to the power switch that causes the power switch to reduce the current flow when the current...
A current mirror suitable, for example, for a charge pump circuit comprises a reference device (21), an output device (22), a first amplifier (41), a follower amplifier (42), and switches (31, 32 43, 44). When switches 31 and 43 are closed, the current mirror is enabled and the low output impedance of follower (42) ensures that the gate voltage of output device (22) quickly equals the gate voltage of reference device (21), switching on the output quickly and accurately. When output device (22) i...
|
|