Patent ID: 6556401
Filing Date: 2003-04-29
Classification: H02H

Abstract:
A voltage overload protection circuit, comprising:first and second input connections for receiving an input voltage signal; first and second output connections for providing an output voltage signal; a first circuit path connecting the first input connection and the first output connection; a second circuit path between the second input connection and the second output connection, and including a source/drain path of a first field-effect transistor for blocking the second circuit path when an overvoltage is present; a third circuit path between the first circuit path and a connection of the first field-effect transistor which is coupled to the second input connection; and a second field-effect transistor having a source/drain path arranged in the third circuit path, which completes the third circuit path if an overvoltage is present between the first and the second input connection; wherein a potential in the first circuit path between the first input connection and the first output connection is input to a gate connection of the first field-effect transistor, whereby an overvoltage occurring at the input connections causes the first field-effect transistor to turn off; and a gate connection of the second field-effect transistor is connected to a potential in the second circuit path between the second output connection and a connection of the first field-effect transistor which is coupled to the second output connection, whereby said second field-effect transistor turns on in response to said first field-effect transistor turning off.