The TISP4xxxJ1BJ is a symmetrical voltage-triggered bidirectional thyristor device which has been designed as the tail (ground return) element of a Y circuit configured protector. As such, the TISP4xxxJ1BJ must be rated to conduct the sum of the TIP and RING currents. For example, the normal GR-1089-CORE testing can impose 200 A, 10/1000 and 1000 A, 2/10 on the ground return element of the Y configuration. Using the TISP4xxxJ1BJ together with two TISP4xxxH3BJ parts gives a 2x 100 A, 10/1000 Y protector circuit. For ITU-T applications, using the TISP4xxxJ1BJ with a TISP3xxxT3BJ gives a coordinated Y protector with a 2x 120 A, 5/310 capability. Design tables are given in the Applications Information section. These SMB package combinations are often more space efficient than single package Y protection multi-chip integrations.