Polarity-safe current supply circuit for electronic components, has voltage displacement circuit that produces potential at control terminal of second transistor based on potential at voltage-drop connection of first transistor

摘要

The circuit (100) has a coupling unit (150) whose output is connected to control terminal of a first transistor (110), and a voltage-to-current converter (140) provided with second transistor (160) for supplying a response current. The voltage-to-current converter also has a voltage displacement circuit (170) connected to the voltage-drop connection of the first transistor and control terminal of the second transistor. The voltage displacement circuit is used to produce a potential at control terminal of second transistor based on the potential at the voltage drop-connection of first terminal. The first transistor is switch for connection between a voltage supply and an electronic component, such that the current of the electronic component flows through the path between the source connection and voltage-drop connection of the first transistor. The voltage-to-current converter produces a rising response current in response to the rising voltage drop in the path between the source connection and voltage-drop connection of the first transistor. The coupling unit is arranged for outputting the response current.