Patent ID: 6252411
Filing Date: 2001-06-26
Classification: G01R

Abstract:
A method of testing a C-section low pass filter, comprising the steps of:(a) providing a C-section low pass filter as a circuit to be tested, the circuit having input and output connections;(b) applying a.c. input test signals from a signal source successively over a range of frequencies to the input connections of the circuit to be tested;(c) measuring, at each frequency the magnitude of the test signal across the input connections of the C-section filter being tested;(d) determining whether the C-section filter has a cut-off frequency in the range of test frequencies;(e) estimating the resistance of a load applied to the output connections of the filter;(f) using the cut-off frequency and the estimate of the load resistance to determine a value representing total circuit capacitance for the C-section filter; and(g) using the total circuit capacitance to determine insertion loss of the filter.