HI-508/883

The HI-508/883 is an eight channel single-ended multiplexer. This monolithic CMOS multiplexer includes an array of eight analog switches, a digital decode circuit for channel selection, a voltage reference for logic thresholds, and an ENABLE input for device selection when several multiplexers are present. The Dielectric Isolation (DI) process used in fabrication of this device eliminates the problem of latch-up. Also, DI offers much lower substrate leakage and parasitic capacitance than conventional junction-isolated CMOS. Switches are guaranteed to break-before-make, so that two channels are never shorted together. The switching threshold for each digital input is established by an internal +5V reference, providing a guaranteed minimum 2. 4V for logic “1” and Maximum 0. 8V for logic “0”. This allows direct interface without pull-up resistors to signals from most logic families: CMOS, TTL, DTL and some PMOS. For protection against transient overvoltage, the digital inputs include a series 200Ω resistor and a diode clamp to each supply. If input overvoltage protection is needed, the HI-548/883 and HI-549/883 multiplexers are recommended. For further information see Application Note AN520.