Patents by Inventor Krishnappa Ranganath

Krishnappa Ranganath has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20010037245
    Abstract: A point of sale device includes a housing; a processor supported by the housing; a printer coupled to the processor and supported by the housing; a display coupled to the processor and supported by the housing; a keypad coupled to the processor and supported by the housing; and a communications interface coupled to the processor and supported by the housing, the communications interface being configured to communicate with a server via the Internet.
    Type: Application
    Filed: April 6, 2001
    Publication date: November 1, 2001
    Inventors: Krishnappa Ranganath, Naveen Mandhana
  • Patent number: 5747942
    Abstract: The electronic ballast for a gas-discharge lamp includes an inverter. The inverter uses the combination of a step-up transformer, a resonant circuit, and clamping diodes to provide an operational inverter output voltage that is independent of the start-up output voltage of the inverter. During the start-up mode, the step-up transformer is used to provide the start-up voltage for the lamp and the resonant circuit is inactive. Clamping diodes prevent or inhibit the resonant circuit from resonating with potential parasitic capacitances during the start-up mode. During the operational mode, an oscillator is tuned relative to the resonant frequency of a resonant circuit to control the brightness of the fluorescent lamp.
    Type: Grant
    Filed: July 10, 1996
    Date of Patent: May 5, 1998
    Assignee: Enersol Systems, Inc.
    Inventor: Krishnappa Ranganath
  • Patent number: 5636266
    Abstract: A wireless caller identification system employing master and remote units. Microcontrollers at both master and remote units facilitate secure communications between units, providing the identity of the source of calls received at the master unit over a connected telephone line from a telephone central office. Radio frequency (RF) or infrared (IR) modes of communication may be used.
    Type: Grant
    Filed: February 15, 1996
    Date of Patent: June 3, 1997
    Assignee: MTI International
    Inventors: Krishnappa Ranganath, Mehul Desai
  • Patent number: 5471117
    Abstract: An inverter circuit operating from line utilizes minimum, lower rating switches to operate at higher frequency, while maintaining substantially unity power factor and lower input current harmonics. The input rectified DC is transferred to a storage capacitor using a buck-boost regulator in which the current in inductor is always maintained discontinuous and proportional to the instantaneous input voltage. Filtering this input current will give substantially sinusoidal current at the input. The second switch in the buck-boost regulator and an additional third switch contributes to the necessary half bridge for an inverter. The inverter, which can be self oscillating or driven from a control circuitry, can give higher frequency, high voltage AC output with ability to control the load power hence provide for dimming, e.g. for a fluorescent lamp.
    Type: Grant
    Filed: May 11, 1994
    Date of Patent: November 28, 1995
    Assignee: MTI International, Inc.
    Inventors: Krishnappa Ranganath, Alexander Kurnia
  • Patent number: 5471119
    Abstract: A lighting system comprising: an AC power line; an electronic ballast including structure for receiving and interpreting commands transmitted on the power line to control dimming of a fluorescent lamp, the ballast including structure defining an individual address, the ballast including structure for initiating an arc to start the fluorescent lamp, for limiting current through the fluorescent lamp after the arc is initiated, and for dimming the light output of the fluorescent lamp; and a control element spaced apart from the electronic ballast and including structure for sending commands on the power line in a format that the ballast is capable of interpreting, the control element including structure for sending an address with the command, the ballast including structure for comparing the sent address with its individual address and responding to the command if the sent address matches its individual address.
    Type: Grant
    Filed: June 8, 1994
    Date of Patent: November 28, 1995
    Assignee: MTI International, Inc.
    Inventors: Krishnappa Ranganath, Alexander Kurnia
  • Patent number: 5394064
    Abstract: An electronic ballast circuit for multiple fluorescent lamps. Control is achieved by varying the voltage and the frequency of operation of an inverter utilized to drive the fluorescent lamps. A separate voltage boost converter provides regulated voltage to the converter. Dimming is accomplished by varying the voltage either manually or in response to sensor circuitry.
    Type: Grant
    Filed: October 15, 1993
    Date of Patent: February 28, 1995
    Assignee: Micro-Technology Inc.-Wisconsin
    Inventors: Krishnappa Ranganath, Alexander Kurnia
  • Patent number: 5349638
    Abstract: An interface circuit used between a telephone office and a subscriber's telephone operated in response to signals identifying incoming calls to provide visual and/or audible indications of the identification information. The incoming signal information is also extended in decoded form to an associated computer, computer network, and/or television screen.
    Type: Grant
    Filed: January 25, 1993
    Date of Patent: September 20, 1994
    Assignee: Micro-Technology Inc.-Wisconsin
    Inventors: Satyan G. Pitroda, Krishnappa Ranganath