Browse Prior Art Database

Esaki Diode Exclusive Or Circuit

IP.com Disclosure Number: IPCOM000097763D
Original Publication Date: 1961-Jun-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 29K

Publishing Venue

IBM

Related People

Gruodis, AJ: AUTHOR [+2]

Abstract

The exclusive OR circuit provides a ground output when either A or B is negative. A positive output is provided when A and B are both positive, or A and B are both negative.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 92% of the total text.

Page 1 of 2

Esaki Diode Exclusive Or Circuit

The exclusive OR circuit provides a ground output when either A or B is negative. A positive output is provided when A and B are both positive, or A and B are both negative.

Esaki diode D1 has low and high voltage states. D2...D6 are conventional diodes. When A is positive, current flows through D5 and R1. No current flows through D3. In a like manner, when B is positive, current flows through the D6 and R2, while no current flows through D4. Therefore, when both A and B are positive,.transistor T1 is cut off and the output approaches the positive level of the supply +V connected to R5.

When A is negative, no current flows through D5, while current is drawn through D3. The current flowing through D3 at this time is drawn through R4, turning T1 on. The collector current of T1 causes a potential drop across R5, resulting in a decrease in the output voltage. At this time, only a small amount of current is drawn through resistor R3, which is insufficient to cause D1 to switch to the high voltage state. A negative signal on B, when input A is positive, results in the same operation since diodes D4 and D6 operate in the same manner as D5 and D3.

When both A and B are negative, both D3 and D4 conduct, drawing current through R3 and R4. Current through R3 together with base current switches D1 to the high voltage state. The voltage drop across D1 at this time is sufficient to cut off conduction in T1. D2 supplies current through R4 at thi...