The Fairchild Switch FSTU3384 provides 10 bits of highspeed CMOS TTL-compatible bus switches. The low on resistance of the switch allows inputs to be connected to outputs without adding propagation delay generating additional ground bounce noise. Both the A Ports and the B Ports are "undershoot hardened" with UHC protection to support an extended input range to 2.0V below ground. Fairchild's integrated Undershoot Hardened Circuit, UHC senses undershoot at the I/Os, and responds by preventing voltage differentials from developing and turning on the switch. The device is organized as two 5-bit switches with separate bus enable (OE) signals. When OE is LOW, the switch is ON and Port A is connected to Port B. When OE is HIGH, the switch is OPEN and a high-impedance state exists between the two ports.