Linear transfer voltage to current circuit
AssigneeHitachi, Ltd.
InventorsKenji Toyota, Tatsuji Matsuura, Kenichi Hase
Life of this patent
Estimating the term…
Abstract
A differential circuit having a relatively simple structure capable of delivering a linear transfer characteristic and expanding an input dynamic range. An increase in magnitude of differential input voltage V.sub.in applied to each gate of differential-pair MOSFETs M1 and M2 in the differential circuit decreases control voltage V.sub.CONT in a control circuit. On the other hand, since a current fed to MOSFETs M3 and M4 in the differential circuit decreases simultaneously, a current supplied to the differential-pair MOSFETs M1 and M2 in the differential circuit increases. Thus, the present invention makes it possible to effectively expand the input dynamic range with respect to differential input voltage V.sub.in.
Claims3
An electronic circuit including a differential circuit comprising first and second field-effect transistors having a differential input voltage applied to each gate thereof and a common source connection therewith,
- said differential circuit comprising:
- third and fourth field-effect transistors which have a common source connection with each source of said first and second field-effect transistors,
- a drain of said first field-effect transistor and a drain of said third field-effect transistor which are connected with one differential output, and
- a drain of said second field-effect transistor and a drain of said fourth field-effect transistor which are connected with the other differential output;
- said electronic circuit further comprising a control circuit having an output node for generating a control voltage which decreases in response to an increase in magnitude of said differential input voltage applied to each gate of said first and second field-effect transistors, and
- wherein said control voltage generated from said output node of said control circuit is supplied to each gate of said third and fourth field-effect transistors of said differential circuit.
Dependencies are inferred from the claim text.