The task is to ensure that the center frequency, once set by laser fuse, will not change within the predefined temperature and supply voltage range. Using the symbolic circuit analysis tool Analog Insydes [2], the objective is to derive a formula for the center frequency of the filter as a The symbolic transfer function of the filter macro model (Figure 2) is derived by using Analog Insydes to set up the circuit equations from a net list description and solve the equations for the output voltage in terms of the macro parameters and the input voltage: