The TMUX1119 has a transmission gate topology, as shown in Figure 7-3. Any mismatch in the stray capacitance associated with the NMOS and PMOS causes an output level change whenever the switch is opened or closed.

Figure 7-3 Transmission Gate Topology

The TMUX1119 has special charge-injection cancellation circuitry that reduces the drain-to-source charge injection to -6pC at V_D = 1V as shown in Figure 7-4.

Figure 7-4 Charge Injection vs Drain Voltage