Circuit for selecting measuring range, e.g. for digital multimeter

摘要

The circuit has a damping element (3) with a measurement parameter (Uin) fed into its input and a controller (27) to determine its damping. A comparator (6) connected to the damping element output (A3) has upper and lower threshold levels and feeds a step switch (15), whose output is connected to the controller. The step switch has a digital counter (21) with its control input (Es) connected to the comparator output (A6a). The electronic controller sets the damping according to the state (Z0,Z1) of the counter.