FSTUD32211

The Fairchild Switch FSTUD32211 provides up to 48-bits of high-speed CMOS TTL-compatible bus switching. Thelow On Resistance of the switch allows inputs to be connected to outputs without adding propagation delay or generating additional ground bounce noise. A diode to VCC has been integrated into the circuit to allow for level shifting between 5V inputs and 3.3V outputs.

The FSTUD32211 can be organized as four 12-bit, two 24-bit, or one 48-bit bus switch. When routed as a 40-bit bus switch, the FSTUD32211 can be organized as four 10-bit, two 20-bit or one 40-bit bus switch. When OE1 is LOW, the switch is ON and Port 1A is connected to Port 1B. When OE2 is LOW, the switch is ON and Port 2A is connected to Port 2B. When OE3 is LOW, the switch is ON and Port 3A is connected to Port 3B. When OE4 is LOW, the switch is ON and Port 4A is connected to Port 4B. When OE1, OE2, OE3, or  OE4 are HIGH, a high impedance state exists between the A and B Ports. The A and B Ports of FSTUD32211 are protected against undershoot 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.