The Hl-518 is a monolithic, dielectrically isolated, high speed, high performance CMOS analog multiplexer. It offers unique built-in channel selection decoding plus an inhibit input for disabling all channels. The dual function of address input A2 enables the Hl-518 to be user programmed either as a single ended 8-Channel multiplexer by connecting `Out A' to `Out B' and using A2 as a digital address input, or as a 4-Channel differential multiplexer by connecting A2 to the Vsupply. The substrate leakages and parasitic capacitances are reduced substantially by using the Intersil Dielectric Isolation process to achieve optimum performance in both high and low level signal applications. The low output leakage current (lD(OFF) < 100pA at 25oC) and fast settling (tSETTLE = 800ns to 0.01%) characteristics of the device make it an ideal choice for high speed data acquisition systems, precision instrumentation, and industrial process control.