Gilbert cell

In electronics, the Gilbert cell is a type of frequency mixer. It produces output signals proportional to the product of two input signals. Such circuits are widely used for frequency conversion in radio systems.[1] The advantage of this circuit is the output current is an accurate multiplication of the (differential) base currents of both inputs. As a mixer, its balanced operation cancels out many unwanted mixing products, resulting in a "cleaner" output.

It is a generalized case of an early circuit first used by Howard Jones in 1963,[2] invented independently and greatly augmented by Barrie Gilbert in 1967.[3] It is a specific example of "translinear" design, a current-mode approach to analog circuit design. The specific property of this cell is that the differential output current is a precise algebraic product of its two differential analog current inputs.

  1. ^ Allen A. Sweet, "Designing Bipolar Transistor Radio Frequency Integrated Circuits", Artech House, 2007, ISBN 1596931280 page 205
  2. ^ Jones, Howard E., "Dual output synchronous detector utilizing transistorized differential amplifiers" Archived 2018-03-11 at the Wayback Machine, U.S. patent 3,241,078A (filed: 18 June 1963; issued: 15 March 1966)
  3. ^ Gilbert, B. (December 1968). "A precision four-quadrant multiplier with subnanosecond response" (PDF). IEEE Journal of Solid-State Circuits. SC-3 (4): 353–365. doi:10.1109/JSSC.1968.1049924. S2CID 6584426. Archived from the original (PDF) on 2020-02-18.