Dual 4:1 mux with 450 Ohm on-resistance
The ADG509AKNZ integrates two independent SP4T switches in a single 16-pin DIP — a 4:1 multiplexer/demultiplexer per channel, giving you eight analog inputs muxed down to two outputs. Each switch leg presents a maximum 450 Ohm on-resistance, and the channel-to-channel matching is held to 22.5 Ohm, so the insertion loss skew between adjacent channels stays tight enough for a 10-bit ADC front-end without external trim. Switching is fast: 300 ns typical for both Ton and Toff, which lets it track a 1.6 MHz sample clock with enough margin for settling before the ADC starts conversion. The 4 pC charge injection means the glitch energy dumped into the signal path at switch transitions is low enough that a downstream sample-and-hold doesn't see a voltage step bigger than ~4 mV into a 1 nF hold cap.
Leakage current is specified at 1 nA max off-channel, so a 10 kOhm source impedance sees less than 10 µV of DC error from the switch leakage alone. Off-channel capacitance (CS(off)) is 5 pF, on-channel (CD(off)) is 11 pF — budget this into the settling time calculation if you're switching at the 300 ns rate into a high-impedance load.
Active lifecycle and RoHS compliance
Analog Devices lists the ADG509AKNZ as Active in production and RoHS3 compliant — no last-time-buy notice or obsolescence risk on the horizon. The 16-DIP (0.300", 7.62mm) through-hole package is a standard board footprint; the tube shipping quantity is the factory default for this leaded package.