Patent ID: 6088209
Filing Date: 2000-07-11
Classification: H02H

Abstract:
A voltage spike suppressor for substantially eliminating voltage transients exceeding peak line voltage of a source of electricity having at least a first and a second terminal, the suppressor comprising:a) a diode network having at least four diodes connected across the terminals of the source;b) a parallel-connected capacitor-resistor network having a pair of capacitors connected in series with each other and a pair of resistors connected in series with each other, with the capacitor pair connected in parallel with the resistor pair and each of the pair of capacitors and resistors have an intermediate terminal therebetween and the respective intermediate terminals are connected together by a short circuit;whereini) a first diode in the diode network has an anode connected to the first terminal and a cathode connected to a first end of the capacitor-resistor network,ii) a second diode in the diode network has a cathode connected to the second terminal and an anode connected to a second end of the capacitor-resistor network,iii) a third diode in the diode network has anode connected to the second terminal and a cathode connected to the first end of the capacitor-resistor network, andiv) a fourth diode in the diode network has a cathode connected to the first terminal and an anode connected to the second end of the capacitor-resistor network such that the diode network provides a current path for energy in an electrical transient on either the first or second terminals to be coupled from the terminals to the capacitor-resistor network to prevent an overvoltage condition at the terminals; andc) a diode clamp circuit having a pair of diodes whereini) a first diode in the diode clamp circuit has a cathode directly connected to the first end of the capacitor-resistor network,ii) a second diode in the diode clamp circuit has an anode directly connected to the second end of the capacitor-resistor network, andiii) an earth ground connected to an anode of the first diode in the diode clamp circuit and a cathode of the second diode in the diode clamp circuit such that common-mode voltage transients at the capacitor-resistor network exceeding the peak line voltage are clamped to earth ground by the diode clamp circuit.