Control circuit for heater plugs of vehicle for protection against polarity reversal, has switching unit provided for activating FET, so that current flow is released in directions of current path that corresponds to polarity of glow plug

摘要

The circuit (10) has a control unit (30) for controlling a glow plug (20), where the control unit has a FET, which is interconnected with the glow plug in a common current path (P). Another FET is connected with the former FET in opposite directions such that current flow is blocked in the current path in both directions (D), where the transistors are designed as P-channel or N-channel FETs. A switching unit (40) is provided for activating the latter FET, so that the current flow is released in the directions of the current path that corresponds to prescribed polarity of the glow plug. An independent claim is also included for a method for controlling heater plugs for protection against polarity reversal.