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An Adaptive Device and Circuit

IP.com Disclosure Number: IPCOM000096060D
Original Publication Date: 1964-Nov-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 19K

Publishing Venue

IBM

Related People

Dill, FH: AUTHOR

Abstract

In adaptive circuits, it is desired that devices be conditioned to have a particular response family for a family of input conditions. The GaAs tunnel diode in a conditioned symmetrical Goto circuit of certain types serves in this capacity.

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An Adaptive Device and Circuit

In adaptive circuits, it is desired that devices be conditioned to have a particular response family for a family of input conditions. The GaAs tunnel diode in a conditioned symmetrical Goto circuit of certain types serves in this capacity.

GaAs tunnel diodes degrade when a forward current of high magnitude is passed through the device. This degradation consists of a decrease in Ip. This is a permanent change. In spite of this degradation, it is possible to operate GaAs tunnel diode circuits for long periods by operating them so that the forward currents are kept small.

The circuit utilizes GaAs tunnel diodes of initially equal, or nearly equal, Ip values and has an even number of inputs. Normal Goto twins must have odd numbers of inputs. The circuits are connected in the usual fashion and operated with three-phase clocks as for normal Goto tunnel diode circuits. This circuit follows the inputs if there is a majority of two. If the inputs divide equally, the tunnel diode with lower peak current switches giving thus a biased output. If the switched output is not the desired form, a plus or minus current can be passed through the conditioning electrode lowering Ip of one diode or the other, changing the bias of the circuit.

After training, such circuits could be replaced by unsymmetrical Ge tunnel diode circuits giving an arrangement of fixed organization. Any twin tunnel-diode circuit and many single tunnel-diode circuits can be used...