A technique is described for improving the sampled current accuracy in current mirror circuits such as are often used to monitor the current output to a load. A reference voltage is established to feedback the load voltage conditions at the output to the current reference circuitry, thereby greatly reducing the error in the reference current over that which is produced by prior art circuits. The technique is shown as applied to a current limiting circuit for driving an output load. An alternativ...

A current-to-current isolator is utilized in a monitoring system between a signal transmitter and a control room instrument. The isolator has a master oscillator, including a first transformer, a slave oscillator, a current transformer and a rectifying circuit, so that the current signal at its input is closely reproduced at its output. The isolator is powered by the signal current from the transmitter and does not require an external power source.

A current difference current source which provides a stable current as operating conditions change. Two MOS transistors operate as two current sources. A difference current is obtained by subtracting the two transistor currents. The two current sources are configured to vary similarly as conditions change, such that their difference remains constant. In the alternative the difference current is forced to decrease as current increases in the transistors, wherein a reverse compensated current is p...

An interleaved small-inductance buck voltage regulator (VRM) converter with the novel current sensing and sharing technology significantly improves transient response with size minimization. Specifically, two or more buck VRM modules are interleaved or connected in parallel. The resultant current waveform has a fast transient response but with reduced ripples since the ripples in the individual modules mathematically cancel one another. The result is a smooth output current waveform having spike...

A stacked current mirror circuit includes four N-channel MOS transistors. One transistor serves as an input device for conducting via its drain, a majority of the reference current. Another transistor is connected as a mirroring device, with its drain coupled to a voltage source, its gate coupled to the gate of the input device, and its source coupled to the source of the input device at a first common node. These two transistors couple to form a first current mirror circuit which couples to the...

A current sensing, self-heating device for protecting equipment against abnormal current levels which is automatically resettable under mild overcurrent conditions and nonresettable under severe overcurrent conditions. The device comprises a thermostat metal assembly with a temperature compensating portion and an actuating portion which is placed adjacent a nonresettable two-position snap-acting blade electrically connected to ground. During normal operation current flows from the line source th...

The emitter current supplied from a transistor is maintained proportionally related by a factor k to current withdrawn from a first resistive network. This is done by applying the collector current of the transistor to a second resistive network having a current-versus-voltage characteristic proportionally related by the factor k to that of the first resistive network, comparing the potentials developed across the first and the second resistive networks in a differential amplifier to develop and...

A current mirror amplifier using a first and a second transistors with parallelled base-emitter circuits and collector electrodes connected to input and output terminals, respectively, includes a degenerative collector-to-base feedback connection with high current gain. Accordingly, input and output direct currents can be accurately proportioned without an inaccuracy caused by base current flows. The feedback connection may comprise a cascade connection of a third transistor and a fourth complem...

A three-terminal current amplifier having a current gain substantially independent of the forward current gains of its component FET's. First and second FET's have source electrodes connected to the common terminal of the amplifier. A third FET has its source electrode connected to the second FET drain electrode and has its gate and drain electrodes connected to the input terminal and the output terminal of the amplifier, respectively. The gate electrodes of the first and second FET's and the fi...

Improved current mirrors are provided by connecting current mirrors of known types in cascode.