摘要 |
A four quadrant multiplier comprises X and Y input stages for coupling signals to a gain core amplifier for multiplication, wherein each of the input stages and the gain core amplifier further comprises a pair of complementary circuits, based on devices having opposite conductivity properties. The complementary X-input stage is a dual differential amplifier which provides balanced, differential outputs when loaded by the gain core differential amplifiers, due to separate cancellation of the npn and pnp base currents within the loaded X-input stage. Outputs from the cross-connected gain core amplifiers provide a pair of complete, ground referenced product signals having opposite phases. The X-input stage is also suitable for driving other complementary, differential stages such as two quadrant multipliers, voltage controlled amplifiers, and high speed analog multiplexing circuits.
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