The Fairchild Switch FSTU32160 is a 16-bit to 32-bit high-speed CMOS TTL-compatible multiplexer/demultiplexer bus switch. The low on resistance of the switch allows inputs to be connected to outputs without adding propagation delay or generating additional ground bounce noise. The device can be used in applications where two buses need to be addressed simultaneously. The FSTU32160 is designed so that the A Port demultiplexes into B1 or B2 or both. The A and B Ports have “undershoot hardened” circuit protection to support an extended range to 2.0V below ground. Fairchild’s integrated Undershoot Hardened Circuit (UHC®) senses undershoot at the I/O’s, and responds by preventing voltage differentials from developing and turning on the switch. Two select (S1, S2) inputs provide switch enable control. When S1, S2 are HIGH, the device precharges the B Port to a selectable bias voltage (Bias V) to minimize live insertion noise.