R.c. Or R.l. Type Patents (Class 331/140)
  • Patent number: 8872593
    Abstract: A technique for calibration of on-chip resistance (R) and capacitance (C) values using an on-board bypass capacitor may include configuring an on-chip switch to selectively couple an on-chip calibration circuit to an on-chip port. The on-chip calibration circuit may include an RC oscillator having an RC time constant (RCTC). The on-board bypass capacitor may be coupled to the on-chip calibration circuit, by using the on-chip port. The on-chip R and C values may be calibrated using the on-chip calibration circuit and the on-board bypass capacitor.
    Type: Grant
    Filed: January 4, 2013
    Date of Patent: October 28, 2014
    Assignee: Broadcom Corporation
    Inventors: Mohyee Mikhemar, Hooman Darabi
  • Patent number: 8120436
    Abstract: In one embodiment, a system for generating an oscillating signal includes a transconductance amplifier comprising a single-ended output and a differential input. The system also includes only one feedback loop coupled to the transconductance amplifier. The feedback loop includes a low pass filter configured to receive the output of the transconductance amplifier. Also, the feedback loop includes a high pass filter configured to receive the output of the first low pass filter and output a signal to only one terminal of the differential input of the transconductance amplifier.
    Type: Grant
    Filed: April 30, 2009
    Date of Patent: February 21, 2012
    Assignee: The Texas A&M University System
    Inventors: Sang Wook Park, Edgar Sánchez-Sinencio
  • Publication number: 20080157890
    Abstract: The present invention is an oscillator including: first transistors outputting oscillation signals of different oscillation frequencies to collectors; a common node to which outputs of emitters of the first transistors are connected and input; a feedback circuit feeding an output of the common node to bases of the first transistors; and isolation circuits that are respectively provided between the emitters of the first transistors and the common node and cut off high frequency components from the common node.
    Type: Application
    Filed: December 27, 2006
    Publication date: July 3, 2008
    Inventors: Toshimasa Numata, Alejandro Puel
  • Patent number: 7157982
    Abstract: In a Wien-Robinson oscillator, a negative feedback path and a positive feedback path are arranged between the output of an operational amplifier and a reference ground potential. The negative feedback path contains two resistors which are connected in series and whose common circuit point is connected to the inverting input of the operational amplifier. The positive feedback path is formed from two RC elements which are connected in series and whose common circuit point is connected to the non-inverting input of the operational amplifier. If the aim is to keep the amplitude of the output voltage from the oscillator constant, additional measures are required, which increase the circuitry complexity. In order to stabilize the output voltage from the oscillator with little complexity, a third resistor is arranged between the output of the operational amplifier and that end of the positive feedback path which faces away from the reference ground potential.
    Type: Grant
    Filed: June 18, 2003
    Date of Patent: January 2, 2007
    Assignee: Bosch Rexroth AG
    Inventor: Karlheinz Panzer
  • Patent number: 7071710
    Abstract: The apparatus for detecting the effects of interconnect resistance and capacitance (RC) in a logic circuit includes a first ring oscillator with the interconnect RC parasitics in a logic circuit and a minimum reference ring oscillator without the interconnect RC parasitic in a logic circuit multiplexed to have common stages to obtain delay with and without the parasitics of the interconnect RC. The frequency difference between the first ring oscillator frequency and the minimum reference ring oscillator frequency is determined to detect the effects of the interconnect RC in the logic circuit.
    Type: Grant
    Filed: August 18, 2004
    Date of Patent: July 4, 2006
    Assignee: Texas Instruments Incorporated
    Inventors: Andrew Marshall, Victor C. Sutcliffe
  • Patent number: 6590463
    Abstract: A RC oscillator circuit with a stable output frequency, having an oscillating integrated circuit working under an operation voltage, the resistor, a first capacitor, a second capacitor, and a transistor. The first and second capacitors construct a RC circuit. The resistor has first and second terminals coupled to output and input terminals of the oscillating integrated device, respectively. The first capacitor has first and second terminals coupled to the input terminal of the oscillating integrated device and the second terminal of the resistor, respectively. The second capacitor has first and second terminals coupled to the second terminal of the first capacitor and ground, respectively. The transistor has a gate coupled to the operation voltage, a drain coupled to the first terminal of the second capacitor, and a grounded source. The RC oscillator circuit with a modulable frequency can work under difference operation voltages and output the same frequency.
    Type: Grant
    Filed: September 27, 2001
    Date of Patent: July 8, 2003
    Assignee: Faraday Technology Corp.
    Inventor: Han-Tsun Lin
  • Patent number: 6504436
    Abstract: A tuning circuit includes an oscillator that receives an oscillating input signal and a control signal, and generates an oscillating output signal. The control signal is obtained from a frequency control circuit that compares the phases of the oscillating output signal and a reference signal. The control signal controls the transconductance of a transconductance element in the oscillator, thereby controlling the oscillator output frequency. The oscillating input signal is obtained from an amplitude control circuit that detects an amplitude limit of the oscillator output. The oscillator output amplitude is responsive to the oscillating input signal. Frequency control and amplitude control in this tuning circuit are mutually independent, so their respective control loops remain stable under all frequency and amplitude combinations.
    Type: Grant
    Filed: May 23, 2001
    Date of Patent: January 7, 2003
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Akira Horikawa, Akira Yoshida, Takashi Taya
  • Patent number: 6005449
    Abstract: An ultra-low power, fast start fuze oscillator contained in a fast moving projectile which contains a programmable projectile fuze. It is an RC oscillator which uses a low power comparator, three biasing resistors, a timing resistor and a timing capacitor to produce an output frequency as low as 8 kHz with a frequency error of less than .+-.0.1% over a -40.degree. C. to +60.degree. C. temperature range. At the same time, it is capable of surviving a high g environment (30,000 g to 60,000 g) in a reliable manner. Furthermore, the oscillator draws a very low amount of power, using a maximum of about 20 uA of current and has a start-up time limited to a maximum of 1.5 msec. An additional circuit can be connected to the positive supply voltage input of a lower current version of an RC oscillator to jump start the RC oscillator, thereby improving start-up time to 1.5 msec while reducing the current drain to 15 uA.
    Type: Grant
    Filed: December 31, 1997
    Date of Patent: December 21, 1999
    Assignee: AAI Corporation
    Inventor: Richard P. Oberlin
  • Patent number: 4485356
    Abstract: A low frequency sinusoidal oscillator, comprises a circuit which contains operational amplifiers, resistors and capacitors and has no inductor. The circuit, however, operates as an inductor. The circuit is arranged to resonate at a frequency which may be chosen by acting on only one component which preferably is a resistive component.
    Type: Grant
    Filed: June 4, 1982
    Date of Patent: November 27, 1984
    Inventor: Lorenzo Fassino
  • Patent number: 4430627
    Abstract: An amplitude control circuit of the invention includes a vector composition circuit (18) for composing a cosine-wave signal (e3) from a sine-wave signal (e1) and a control signal generation circuit (20) for providing a control signal (e4) from the sine- and cosine-wave signals (e1, e3) which the control signal (e4) has substantially no ripples. DC level of the control signal (e4) is varied proportional to the amplitude of the sine-wave signal (e1) regardless of the frequency of the sine-wave signal (e1). The amplitude of an amplification control circuit (12) is controlled by the control signal (e4) so that the amplitude of the oscillation output signal (e1) derived from the oscillation circuit (16) is constant.
    Type: Grant
    Filed: June 3, 1980
    Date of Patent: February 7, 1984
    Inventor: Kenji Machida
  • Patent number: 4188593
    Abstract: An RC oscillator comprising an amplifier with a first RC voltage divider coupling its output circuit to its non-inverting input circuit and a second RC voltage divider coupling its non-inverting input circuit to its inverting input circuit. The first RC voltage divider comprises a series RC network in its series arm and parallel RC network in its shunt leg. The second RC voltage divider has a capacitor in its series arm and a resistor in its shunt leg.
    Type: Grant
    Filed: September 11, 1978
    Date of Patent: February 12, 1980
    Assignee: RCA Corporation
    Inventor: Leonard A. Kaplan
  • Patent number: 4091341
    Abstract: The invention relates to electrical oscillators arranged to oscillate so as to produce a substantially sinusoidal output signal. The said oscillator includes a general impedance transvertor circuit arrangement having two differential amplifiers connected only to a plurality of resistive and capacitive impedance elements and arranged to simulate a tuned circuit with sufficient feedback to maintain oscillation within the tuned circuit. The transvertor circuit is an active device in the form of an impedance invertor circuit or a convertor circuit.
    Type: Grant
    Filed: June 9, 1976
    Date of Patent: May 23, 1978
    Assignee: The Post Office
    Inventors: Alan John Greaves, Phillip Ernest Greenaway, John Mortimer Rollett
  • Patent number: 4091340
    Abstract: The invention relates to electrical oscillators arranged to oscillate so as to produce a substantially sinusoidal output signal. The said oscillator includes a general impedance transvertor circuit arrangement having two differential amplifiers connected only to a plurality of resistive and capacitive impedance elements and arranged to simulate a tuned circuit with sufficient feedback to maintain oscillation within the tuned circuit. The transvertor circuit is an active device in the form of an impedance invertor circuit or a convertor circuit.
    Type: Grant
    Filed: June 9, 1976
    Date of Patent: May 23, 1978
    Assignee: The Post Office
    Inventors: Alan John Greaves, Phillip Ernest Greenaway, John Mortimer Rollett
  • Patent number: 3933046
    Abstract: By including four resistors and a capacitor in a bridge and connecting the bridge to the input terminals and the output terminals of a comparator amplifier a relaxation oscillator is obtained the square-wave frequency of which depends logarithmically upon the ratio of two resistances. Linearization is obtained by using a measuring-value transducer the resistance of which depends exponentially upon a physical quantity, such as temperature, as one of the resistors. The converter may be used in frequency-analog transmission of measuring values and in measuring instruments for measuring-value indication without the need for linearizing steps.
    Type: Grant
    Filed: February 15, 1973
    Date of Patent: January 20, 1976
    Assignee: U.S. Philips Corporation
    Inventor: Dietrich Meyer Ebrecht