The CD4066BPWR is a Texas Instruments quad bilateral FET switch from the 4000B series, containing four independent SPST switches that conduct analog or digital signals in either direction. Each switch passes signals rail-to-rail, and the bilateral topology lets you use them as multiplexers, sample-hold gates, or modulator switches without worrying about signal polarity.
The 4000B series CMOS construction keeps leakage low at high temperature — a practical advantage over older 4000A parts when the ambient hits 125°C.
Housed in a 14-TSSOP (4.40 mm width) surface-mount package, the CD4066BPWR fits on compact PCBs where board area is tight. The TSSOP footprint is standard across many 14-pin analog switches, so swapping to a pin-compatible alternative (e.g., a 74HC4066 in the same package) is straightforward if supply dictates a change.
For new designs, there is no LTB risk and the part can be qualified into the BOM with confidence.