Patents by Inventor Thomas Riedger

Thomas Riedger 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).

  • Patent number: 5041777
    Abstract: A current supply arrangement includes a power transistor (T1) driven by a control transistor (T2). The power transistor switching path is connected between a terminal (UE+) of an unregulated input direct voltage (UE) and a terminal (UA+) of a regulated supply voltage (UA). A first control amplifier (OP1), drives the control transistor via a first electrode (base) thereof and compares a voltage derived from the supply voltage (UA) with a first reference voltage (Uref). A second control amplifier (OP2) compares a measuring voltage (UM) derived at a current measuring resistor (R10) with a second reference voltage. The voltage control and current regulation results in a system having a small number of elements and a sufficient dynamic control range.
    Type: Grant
    Filed: September 21, 1990
    Date of Patent: August 20, 1991
    Assignee: U.S. Philips Corporation
    Inventor: Thomas Riedger
  • Patent number: 4742316
    Abstract: A pulse-width modulator comprising a square-wave generator which triggers a monostable multivibrator driven by a controllable constant current source, the multivibrator having a capacitor as a timing element. The output of the multivibrator controls a gate circuit to which the square wave is also applied, thereby controlling the width of the square wave output from the gate circuit. The modulator can be assembled from standard CMOS building blocks and several external components, thereby achieving a power dissipation below 10 mW. If the current source is controlled by a CMOS variable-gain amplifier, the modulator can serve as the control circuit of a clocked direct voltage converter having internal losses below 25 mW.
    Type: Grant
    Filed: April 13, 1987
    Date of Patent: May 3, 1988
    Assignee: U.S. Philips Corporation
    Inventor: Thomas Riedger