HIGH-ACCURACY FOUR-QUADRANT MULTIPLIER WHICH ALSO IS CAPABLE OF FOUR-QUADRANT DIVISION

摘要

ABSTRACT OF THE DISCLOSUREA four-quadrant analog multiplier comprising afirst pair of transistors to handle one multiplier inputand second and third pairs of transistors interconnectedwith said first pair to effect multiplication. Resistorsare connected to the bases of the second and third pairsof transistors, and current which is proportional-to-absolute-temperature is caused to flow through the resis-tors. The resistors are laser-trimmed until VBE mismatchdistortion is nulled. An op amp is used to drive the basesof all three pairs of transistors. A current source isconnected to the first pair of transistors, and is separ-ately controlled so as to provide for four-quadrant divi-sion. A number of additional features are incorporatedto further minimize distortion and to improve performancein other respects.