Positive current source

Details Positive current source Positive current source

1997-05-23

1998-09-22

Callahan, Timothy P.

Miscellaneous active electrical nonlinear devices, circuits, and

Specific identifiable device, circuit, or system

With specific source of supply or bias voltage

327530, 327538, 327103, 323312, G05F 304

Patent

active

058120203

ABSTRACT:
A positive current source (PCS) for supplying common mode current. The PCS includes a pair of unity gain inverting single ended amplifiers that are connected in antiparallel across a pair of matched resistors. Alternately, the resistors can be connected across the inverting and non-inverting sides of a differential amplifier. A constant voltage is applied across the resistors to supply the common mode current (I.sub.cm) while maintaining a common mode resistance of R/2 and a differential mode resistance approaching infinity. The PCS has a common mode resistance which is small enough to maintain a stable common mode operating point with process variations providing minimal impact.

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