公开(公告)号：US06418042B1

公开(公告)日：2002-07-09

申请号：US09150517

申请日：1998-09-09

Applicant: Varadarajan Srinivasan ,  Bindiganavale S. Nataraj ,  Sandeep Khanna

Inventor： Varadarajan Srinivasan ,  Bindiganavale S. Nataraj ,  Sandeep Khanna

IPC: G11C1500

CPC classification number: G11C15/04 ,  G11C15/00

Abstract: A content addressable memory (CAM) device. The CAM device is a synchronous device that may perform all of the following operations all in one clock cycle: (1) receive comparand data from a comparand bus; (2) receive an instruction from an instruction bus instructing the CAM device to compare the comparand data with a first group of CAM cells in a CAM array; (3) perform the comparison of the comparand data with the first group of CAM cells; (4) generate a match address for a location in the CAM array that stores data matching the comparand data; (5) access data stored in a second group of the CAM cells in the CAM array, wherein the second group of CAM cells may store data associated with the matched location; and (6) output to an output bus the match address, the data stored in the second group of CAM cells, and/or status information corresponding to the matched address or the second group of CAM cells. The status information may include a match flag, multiple match flag, full flag, skip bit, empty bit, or a device identification for the CAM device. The CAM array may also include ternary CAM cells that are individually maskable so as to effectively store either a logic one, logic zero, or a don't care state for compare operations.

Abstract translation: 内容可寻址存储器（CAM）设备。 CAM设备是同步设备，其可以在一个时钟周期内执行所有以下操作：（1）从比较总线接收比较数据; （2）从指令总线接收指令，指示CAM设备将比较数据与CAM阵列中的第一组CAM单元进行比较; （3）比较数据与第一组CAM单元进行比较; （4）生成CAM阵列中存储与比较数据匹配的数据的位置的匹配地址; （5）访问存储在CAM阵列中的CAM单元的第二组中的数据，其中第二组CAM单元可以存储与匹配位置相关联的数据; 和（6）向输出总线输出匹配地址，存储在第二组CAM单元中的数据和/或与匹配地址或第二组CAM单元相对应的状态信息。 状态信息可以包括用于CAM设备的匹配标志，多重匹配标志，满标志，跳过位，空位或设备标识。 CAM阵列还可以包括可单独屏蔽的三进制CAM单元，以便有效地存储逻辑1，逻辑0或用于比较操作的无关状态。

公开(公告)号：US06249467B1

公开(公告)日：2001-06-19

申请号：US09590779

申请日：2000-06-08

Applicant: Jose Pio Pereira ,  Varadarajan Srinivasan ,  Bindiganavale S. Nataraj ,  Sandeep Khanna

Inventor： Jose Pio Pereira ,  Varadarajan Srinivasan ,  Bindiganavale S. Nataraj ,  Sandeep Khanna

IPC: G11C700

CPC classification number: G11C15/04 ,  G11C15/00 ,  G11C29/785 ,  G11C29/816

Abstract: A CAM device that allows defective rows in one CAM block to be functionally replaced by spare rows from any CAM block in the device. In some embodiments, the CAM device includes a main address decoder, a plurality of CAM blocks, a corresponding plurality of spare address decoders, and a block select circuit. In one embodiment, each CAM block includes a main CAM array having a plurality of rows of CAM cells each coupled to a corresponding word line, and a spare row of CAM cells coupled to a spare word line. Each spare row may be used to functionally replace a defective row in the same CAM block or in any other CAM block by programming the address of the defective row into the corresponding spare address decoder. During subsequent read or write operations, an input address is compared with the programmed addresses stored in the spare address decoders. If there is match, thereby indicating that the selected row is defective and has been replaced, the address decoder storing the matching programmed address enables the spare row in the corresponding CAM block, and the block select circuit enables the corresponding CAM block for the operation, so that the read or write operation accesses the spare row instead of the defective row. If there is not a match, the spare address decoder does not enable the corresponding spare word line, and the block select circuit enables the CAM block identified by the input address for the operation.

Abstract translation: CAM设备允许一个CAM块中的有缺陷的行由设备中任何CAM块的备用行功能替换。 在一些实施例中，CAM设备包括主地址解码器，多个CAM块，对应的多个备用地址解码器和块选择电路。 在一个实施例中，每个CAM块包括具有多个CAM单元的行的主CAM阵列，每个CAM单元耦合到对应的字线，以及耦合到备用字线的一组备用的CAM单元。 每个备用行可以用于通过将缺陷行的地址编程到相应的备用地址解码器中来功能地替换同一CAM块或任何其他CAM块中的有缺陷的行。 在随后的读取或写入操作期间，将输入地址与存储在备用地址解码器中的编程地址进行比较。 如果存在匹配，从而指示所选行有缺陷并被替换，则存储匹配的编程地址的地址解码器使能相应CAM块中的备用行，并且块选择电路使能相应的CAM块进行操作， 使得读取或写入操作访问备用行而不是有缺陷的行。 如果不匹配，则备用地址解码器不启用相应的备用字线，并且块选择电路使能由输入地址识别的CAM块用于操作。

公开(公告)号：US6166939A

公开(公告)日：2000-12-26

申请号：US351541

申请日：1999-07-12

Applicant: Bindiganavale S. Nataraj ,  Varadarajan Srinivasan ,  Sandeep Khanna

Inventor： Bindiganavale S. Nataraj ,  Varadarajan Srinivasan ,  Sandeep Khanna

IPC: G11C15/00 ,  G11C15/04

CPC classification number: G11C15/04 ,  G11C15/00

Abstract: Match line control circuits are used to selectively charge corresponding match lines in response to the valid bits. If the valid bit is asserted, thereby indicating the valid data is stored in the CAM row, the match line control circuit pre-charges the match line to enable the match line to be responsive to compare operation between a comparand word and data stored in the row. If the valid bit is de-asserted, thereby indicating that any data stored in the row is invalid, the match line control circuit disables the match line by forcing a mismatch condition between the comparand word and data stored in the row. In one embodiment, the match line control circuit includes a pull-up transistor coupled between the match line and a supply voltage and having a gate responsive to the valid bit. In other embodiments, the match line control circuit further includes a pull-down transistor coupled between the match line and a supply voltage and having a gate responsive to a complement of the valid bit.

Abstract translation: 匹配线控制电路用于响应于有效位选择性地对相应的匹配线进行充电。 如果有效位被断言，则由此指示有效数据被存储在CAM行中，匹配线路控制电路对该匹配线进行预充电以使匹配线能够响应于比较字与存储在 行。 如果有效位被取消置位，从而指示存储在该行中的任何数据无效，则匹配线控制电路通过强制比较字与存储在该行中的数据之间的失配条件来禁用匹配线。 在一个实施例中，匹配线控制电路包括耦合在匹配线和电源电压之间的上拉晶体管，并具有响应于有效位的栅极。 在其他实施例中，匹配线控制电路还包括耦合在匹配线和电源电压之间并具有响应于有效位的补码的门的下拉晶体管。

公开(公告)号：US6154384A

公开(公告)日：2000-11-28

申请号：US439317

申请日：1999-11-12

Applicant: Bindiganavale S. Nataraj ,  Sandeep Khanna ,  Varadarajan Srinivasan

Inventor： Bindiganavale S. Nataraj ,  Sandeep Khanna ,  Varadarajan Srinivasan

IPC: G11C15/04 ,  G11C15/00

CPC classification number: G11C15/04

Abstract: A ternary content addressable memory (CAM) cell. For one embodiment, the ternary CAM cell includes a first memory cell, a compare circuit, a second memory cell and a mask circuit. The first memory cell is coupled to a first pair of bit lines that carries data to and from the first memory cell. The compare circuit receives comparand data on a pair of compare signal lines, and compares the comparand data with the data stored in the first memory cell. The compare circuit includes a pair of transistors and a match transistor. The pair of transistors receives the comparand data on the compare signal lines and also receives the data stored in the first memory cell. The match transistor determines the state of a match line. The second memory cell stores mask data that may mask the comparison result such that it does not affect the logical state of the match line.

Abstract translation: 三元内容可寻址存储器（CAM）单元。 对于一个实施例，三元CAM单元包括第一存储单元，比较电路，第二存储单元和掩模电路。 第一存储器单元耦合到第一对位线，其将数据传送到第一存储器单元并从第一存储单元传送数据。 比较电路在一对比较信号线上接收比较数据，并将比较数据与存储在第一存储单元中的数据进行比较。 比较电路包括一对晶体管和匹配晶体管。 该对晶体管在比较信号线上接收比较数据，并且还接收存储在第一存储单元中的数据。 匹配晶体管确定匹配线的状态。 第二存储器单元存储可以掩蔽比较结果使得其不影响匹配线的逻辑状态的掩码数据。

公开(公告)号：US6148364A

公开(公告)日：2000-11-14

申请号：US001110

申请日：1997-12-30

Applicant: Varadarajan Srinivasan ,  Bindiganavale S. Nataraj ,  Sandeep Khanna

Inventor： Varadarajan Srinivasan ,  Bindiganavale S. Nataraj ,  Sandeep Khanna

IPC: G11C15/00 ,  G11C15/04 ,  G06F12/02

CPC classification number: G11C15/04 ,  G11C15/00

Abstract: A method and apparatus for cascading content addressable memory (CAM) devices is disclosed. The method and apparatus may be particularly useful when depth cascading CAM devices that operate in a flow-through mode. In the flow-through mode, a compare instruction may be simultaneously provided to each CAM device in the cascade, and the match address, data stored at the matched location, or other status information may then be output to a common output data bus by the highest priority matching CAM device in the same cycle that the instruction is provided to the CAM devices. Each CAM device may have a cascade input and a cascade output to perform the cascade function. The cascade output of a higher priority CAM device may be connected to the cascade input of the next lower priority CAM device. The higher priority CAM device may assert a cascade signal on its cascade output at a predetermined time after receiving an input signal (e.g., a clock signal). Asserting the cascade signal may indicate that the higher priority CAM device has completed the compare instruction. When the lower priority CAM device detects that the cascade signal has been asserted on its cascade input, the lower priority CAM device may sample the match flag of the higher priority CAM device to determine if the lower priority CAM device may output its data to the common output data bus.

Abstract translation: 公开了用于级联内容可寻址存储器（CAM）设备的方法和装置。 当以流通模式操作的深度级联CAM设备时，该方法和设备可能是特别有用的。 在流通模式中，可以在级联中同时向每个CAM设备提供比较指令，并且匹配地址，存储在匹配位置的数据或其他状态信息然后可以被输出到公共输出数据总线 在CAM指令提供给CAM设备的同一周期内，最高优先级的匹配CAM设备。 每个CAM设备可以具有级联输入和级联输出以执行级联功能。 较高优先级的CAM设备的级联输出可以连接到下一个较低优先级的CAM设备的级联输入。 较高优先级的CAM设备可以在接收到输入信号（例如，时钟信号）之后的预定时间在其级联输出上断言级联信号。 断开级联信号可能表明较高优先级的CAM设备已经完成了比较指令。 当较低优先级的CAM设备检测到级联信号已经在其级联输入上被断言时，较低优先级的CAM设备可以对较高优先级的CAM设备的匹配标志进行采样，以确定较低优先级的CAM设备是否可以将其数据输出到公共 输出数据总线。

公开(公告)号：US12268448B1

公开(公告)日：2025-04-08

申请号：US17360785

申请日：2021-06-28

Applicant: Sandeep Khanna

Inventor： Sandeep Khanna

IPC: A61B3/10 ,  A61B3/00 ,  A61B3/135 ,  A61B3/14 ,  G16H40/67 ,  G16H80/00

Abstract: The proposed technology includes ophthalmic apparatuses and systems that allow transmission of a digital slit-lamp output (both of the visible light as well as of infra-red wavelength) over the web in “real-time” alongside face-to-face audio-visual communication between the various parties. The digital output of the camera will be in a format that is compatible with direct transmission over the web. This allows a person(s) at the remote site to see the slit-lamp imagery as if the remote examiner(s) were on site in the presence of the patient and simultaneously video-chat with the operator of the microscope to provide tele-consultation. The features also facilitate collaborative care between several providers, as well as patient representative(s), by enhancing the audio-visual communication between parties with the actual slit lamp imagery of the patient in real time.

公开(公告)号：US08913412B1

公开(公告)日：2014-12-16

申请号：US13306896

申请日：2011-11-29

Applicant: Sandeep Khanna ,  Bindiganavale S. Nataraj ,  Varadarajan Srinivasan

Inventor： Sandeep Khanna ,  Bindiganavale S. Nataraj ,  Varadarajan Srinivasan

IPC: G11C15/04

CPC classification number: G11C15/04

Abstract: A content addressable memory (CAM) device having any number of rows, each of the rows including a match line connected to a plurality of CAM cells, a match line detector circuit, and an incremental match line charge circuit. The detector circuit generates a feedback signal based on a detected match line voltage. The charge circuit partially pre-charges the match line to an intermediate voltage during a pre-charge phase of a compare operation, and then selectively charges the match line higher towards a supply voltage in response to the feedback signal.

Abstract translation: 具有任意行数的内容可寻址存储器（CAM）器件，每行包括连接到多个CAM单元的匹配线，匹配线检测器电路和增量匹配线充电电路。 检测器电路基于检测到的匹配线电压产生反馈信号。 充电电路在比较操作的预充电阶段期间将匹配线部分预充电到中间电压，然后响应于反馈信号而选择性地将匹配线充电到电源电压。

公开(公告)号：US08774389B2

公开(公告)日：2014-07-08

申请号：US11225573

申请日：2005-09-13

Applicant: Steven M. Kagan ,  Sandeep Khanna ,  John Arthur Ricketts ,  William M. Thompson

Inventor： Steven M. Kagan ,  Sandeep Khanna ,  John Arthur Ricketts ,  William M. Thompson

IPC: H04M3/00 ,  H04M5/00

CPC classification number: H04M3/5237 ,  H04M3/5232 ,  H04M2203/404

Abstract: A method and system to optimally route telephone calls between shared service centers is presented. Using a combination of service tiers, Agent Directory, Instant Messaging (IM), and Voice over Internet Protocol (VoIP) provides optimal routing of incoming calls for assistance. The method utilizes different protocols during normal operations, transitional operations, and emergency operations, and addresses Shared Service Center (SSC) planning and management.

Abstract translation: 提出了一种在共享服务中心之间优化路由电话呼叫的方法和系统。 使用服务层，代理目录，即时消息（IM）和互联网语音协议（VoIP）的组合可提供呼入呼叫的最佳路由以进行协助。 该方法在正常操作，过渡操作和应急操作中使用不同的协议，并且涉及共享服务中心（SSC）规划和管理。

公开(公告)号：US08631195B1

公开(公告)日：2014-01-14

申请号：US12132053

申请日：2008-06-03

Applicant: Sandeep Khanna ,  Maheshwaran Srinivasan ,  Mark Birman

Inventor： Sandeep Khanna ,  Maheshwaran Srinivasan ,  Mark Birman

IPC: G06F12/00

CPC classification number: G11C15/00 ,  G11C15/04 ,  G11C15/046

Abstract: A search system for detecting whether one or more overlapping sequences of input characters match a regular expression including a prefix string preceding an intermediate expression having a quantified number m of characters belonging to a specified character class is disclosed. The search system includes a CAM array for storing the regular expression, a shift register for counting sequences of input characters that match the character class, and a control circuit that enables the shift register in response to a prefix match and increments the shift register in response to character class matches.

Abstract translation: 公开了一种用于检测输入字符的一个或多个重叠序列与包含具有属于指定字符类的字符的量化数字m的中间表达式之前的前缀字符串的正则表达式相匹配的搜索系统。 搜索系统包括用于存储正则表达式的CAM阵列，用于对与字符类匹配的输入字符的序列进行计数的移位寄存器以及响应于前缀匹配使移位寄存器能够响应的递增移位寄存器的控制电路 到角色类比赛。

公开(公告)号：US08433713B2

公开(公告)日：2013-04-30

申请号：US11136009

申请日：2005-05-23

Applicant: Changsheng Chen ,  Adam Hyder ,  Sandeep Khanna

Inventor： Changsheng Chen ,  Adam Hyder ,  Sandeep Khanna

IPC: G06F17/30 ,  G06F7/00

CPC classification number: G06Q10/10

Abstract: A job searching and matching system and method is disclosed that gathers job seeker information in the form of job seeker parameters from one or more job seekers, gathers job information in the form of job parameters from prospective employers and/or recruiters, correlates the information with past job seeker behavior, parameters and behavior from other job seekers, and job parameters and, in response to a job seeker's query, provides matching job results based on common parameters between the job seeker and jobs along with suggested alternative jobs based on the co-relationships. In addition, the system correlates employer/recruiter behavior information with past employer/recruiter behavior, parameters and information concerning other job seekers, which are candidates to the employer, and resume parameters, and, in response to a Employer's query, provides matching job seeker results based on common parameters between the job seeker resumes and jobs along with suggested alternative job seeker candidates based on the identified co-relationships.