Latch-Up is a condition where a low impedance path is created between a supply pin and ground. This condition is caused by a trigger (current injection or overvoltage), but once activated, the low impedance path remains even after the trigger is no longer present. This low impedance path may cause system upset or catastrophic damage due to excessive current levels. The Latch-Up condition typically requires a power cycle to eliminate the low impedance path.
In the TMUX8108 and TMUX8109 devices, an insulating oxide layer is placed on top of the silicon substrate to prevent any parasitic junctions from forming. As a result, the devices are latch-up immune under all circumstances by device construction.