8:1 analog multiplexer — signal routing for harsh environments
The CD4051BPWRG4 from Texas Instruments is a single 8:1 CMOS analog multiplexer/demultiplexer, meaning it routes one of eight analog or digital signals to a common output (or vice versa). The 8:1 configuration is the standard building block for data acquisition, sensor scanning, and test equipment channel selection. The 16-TSSOP package keeps the board footprint compact for dense channel cards.
The 240 Ohm maximum on-state resistance (Ron) sets the insertion loss for the analog path. In a 10 kOhm load, the Ron adds about 2.3 % attenuation — acceptable for most 8-bit to 10-bit systems, but for precision 12-bit+ designs you'll want to account for the voltage divider effect or buffer the output. The 5 Ohm channel-to-channel matching helps keep gain errors consistent across the multiplexer channels. The 20 MHz -3 dB bandwidth is enough for audio-frequency signals and low-speed data acquisition up to a few MHz. For video or RF switching, the bandwidth and the 30 pF drain capacitance will roll off the signal — this part is best kept in the sub-1 MHz analog or digital multiplexing space.
Supply flexibility — single or dual rails
The CD4051BPWRG4 operates from either a single supply (3 V to 20 V) or dual supplies (±2.5 V to ±9 V). Dual supplies let you switch bipolar signals (e.g., ±5 V audio) without level-shifting. The single-supply range covers standard 5 V and 12 V logic and analog rails commonly found in industrial PLCs and sensor interfaces.
There is no announced last-time-buy or obsolescence notice.