US 11,783,878 B2
Time division multiplexing (TDM) based optical ternary content addressable memory (TCAM)
Thomas Van Vaerenbergh, Diegem Flemish Brabant (BE); Can Li, Palo Alto, CA (US); and Catherine Graves, Milpitas, CA (US)
Assigned to Hewlett Packard Enterprise Development LP, Spring, TX (US)
Filed by Hewlett Packard Enterprise Development LP, Houston, TX (US)
Filed on Nov. 4, 2021, as Appl. No. 17/453,585.
Application 17/453,585 is a continuation of application No. 16/905,694, filed on Jun. 18, 2020, granted, now 11,200,929.
Prior Publication US 2022/0059147 A1, Feb. 24, 2022
Int. Cl. G11C 7/22 (2006.01); G11C 7/10 (2006.01); G11C 15/04 (2006.01); G11C 13/04 (2006.01); G11C 11/42 (2006.01)
CPC G11C 7/222 (2013.01) [G11C 7/1012 (2013.01); G11C 7/1054 (2013.01); G11C 7/1081 (2013.01); G11C 11/42 (2013.01); G11C 13/04 (2013.01); G11C 15/04 (2013.01)] 10 Claims
OG exemplary drawing
 
1. An optical ternary content addressable memory (TCAM) comprising:
an input encoder configured to encode a search word on an optical search signal, wherein each bit position of the search word is represented by at least two time slots of a clock signal;
a programming controller communicatively coupled to a modulator configured to represent a TCAM stored word;
an input routing element configured to optically couple the optical search signal to the modulator; and
an output routing element comprising a first end coupled to the modulator and a second end coupled to a photodetector, the output routing element configured to optically couple a result optical signal from the modulator to the photodetector,
wherein the programming controller is configured to generate an electrical drive signal to control a state of the modulator during each time slot of the clock signal, wherein each bit position of the TCAM stored word is represented by at least two time slots of the clock signal, and wherein the photodetector is configured to detect a mismatch between the optical search signal and the TCAM stored word by detecting light during at least one time slot of the clock signal.