Interconnect Routing on Two Signal Layers of a Modal Reservation PCB: a Case Study

The paper presents a quasistatic simulation of the method of tracing interconnects on two signal layers of a printed circuit board (PCB) with modal reservation (MR) performed in the TALGAT and ADS systems jointly used to determine the application scope of the method in the design of modern electronic equipment. The protective characteristics are analyzed without taking into account losses in the TALGAT system. It is shown that when the ratio of the lengths of the structures located on the outer and inner layers is equal to 0.9, the probability of all types of failures (described by N-norms) over the entire structure length is smaller than for ratios of 0.1 and 0.3. Signal integrity was analyzed in the ADS system, taking into account losses in conductors and dielectrics. For the structure under study, the lowest cutoff frequency was 440 MHz. With an increase in the length ratio between structures with conductors on the outer and inner layers, the signal integrity deteriorates greatly. The simulation results obtained both in TALGAT and ADS are compared, with losses in conductors and dielectrics taken into account. Voltage ware forms are presented for three cases (0.1, 0.3, and 0.9) of the length ratio for the structures located on the outer and inner layers. The maximum amplitude difference is 3%. Thus, the data obtained in TALGAT and ADS for specific tasks can be used jointly in analyzing the method of tracing interconnections on two signal layers of the PCB with MR.