| 摘要 |
Method and corresponding apparatus for liquid level detection with a liquid level detection unit (10) with a capacitive liquid level detector (14) with a input capacitance (C) changing if the capacitive liquid level detector (14) contacts a liquid, the method comprising the steps of: generating a clock signal (CLK), with a predetermined on-time (t1) corresponding to a predetermined sensitivity of the capacitive liquid level detector (14), being fed both to a reference generator (12) and to the capacitive liquid level detector (14); said reference generator (12) generating a control value (CV), derived from an on/off ratio of said clock signal (CLK) and feeding it into a control input (19) of a comparator (18); feeding a liquid detection response signal (RS), of said capacitive liquid level detector (14) in response to said clock signal (CLK), into a signal input (20) of the comparator (18); said comparator (18) triggering an output signal at an output (21) when said liquid detection response signal (RS) exceeds a threshold value (TV) in response to a change of the input capacitance (C). |
