Current switching circuit operable at high speed without externally supplied reference bias
AssigneeNEC Corporation
InventorTomio Takiguchi
Life of this patent
Estimating the term…
Abstract
A constant current source is connected to a first node that connects on the one hand to a predetermined potential via a first switching transistor with a control electrode thereof connected to a signal input terminal, a second node, and a resistive conduction member, and on the other hand to a current output terminal via a second switching transistor with a control electrode thereof connected to the second node to constitute a current switching circuit operable without an external reference bias and with a reduced number of components.
Claims6
A current switching circuit having a signal input terminal and a current output terminal, the current switching circuit comprising:
- a first node;
- a constant current source connected to said first node;
- a first switching transistor connected between the first node and a second node, the first switching transistor having a first control electrode, said first control electrode being connected to the signal input terminal;
- a second switching transistor connected between the first node and the current output terminal, the second switching transistor having a second control electrode, said second control electrode being connected to the second node;
- and
- a resistive conduction member interconnected between the second node and a predetermined potential for a resistive current conduction therebetween.
A decoder current switching circuit comprising;
- a plurality of current switching circuits, each of said plurality comprising:
- a first node;
- a constant current source connected to the first node:
- a first switching transistor connected between the first node and a second node, the first switching transistor having a first control electrode, said first control electrode being connected to the signal input terminal;
- a second switching transistor connected between the first node and the current output terminal, the second switching transistor having a second control electrode, said second control electrode being connected to the second node;
- and
- a resistive conduction member interconnected between the second node and a predetermined potential for a resistive current conduction therebetween;
- and
- a decoder having a plurality of bit-representative signal output terminals each respectively connected to the signal input terminal of a corresponding one of said plurality of current switching circuits;
- and
- a common output terminal connected to each of said current output terminals of said plurality of current switching circuits.
Dependencies are inferred from the claim text.