8.3.2 Ultra-low Charge Injection

The TMUX6119 is implemented with simple transmission gate topology, as shown in Figure 31. 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 31. Transmission Gate Topology

The TMUX6119 utilizes special charge-injection cancellation circuitry that reduces the source (SA or SB)-to-drain (D) charge injection to as low as 0.19 pC at V_S = 0 V, as shown in Figure 32.

Figure 32. Charge Injection vs Source Voltage

The drain (D)-to-source (SA or SB) charge injection becomes important when the device is used as a demultiplexer (demux), where D becomes the input and Sx becomes the output. Figure 33 shows the drain-to-source charge injection across the full signal range.

Figure 33. Charge Injection vs Drain Voltage