| 摘要 |
A calibration configuration for setting an adjustable impedance has a voltage divider with a variable resistor and a resistor connected in series, which circuit is supplied with potentials of a supply voltage and has, between the resistors, a partial voltage tap off terminal. A circuit has a further resistor, whose value is in a fixed relationship with a resistance of the first voltage divider resistor, and generates a voltage dependent upon a value derived from the further resistor. The voltage and the partial voltage are fed to a comparator for outputting a comparison result to a downstream control logic unit, which logic unit is coupled to the resistor of the first voltage divider and generates a control signal dependent upon the comparator output signal. The control logic unit control signal is used to set the variable resistor until the voltages fed to the comparator correspond to one another.
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