Bus Switches Squeeze Into Tight Quarters

Designed for space-constrained portable electronics, four wide-bit bus switches in 40-pin and 48-pin QVSOPs are said to be 41% smaller than standard TSSOPs. Two of the 48-pin switches, the 20-bit FSTU32X384 and 20-bit FSTU16862, employ a patented undershoot hardened circuitry (UHC), which senses undershoot levels down to -2V on any I/O data port and prevents voltage differentials from turning on the switch. All four devices operate from a 5V supply. This includes the 48-pin FST33X257 quad, 24:12 multiplexer/demultiplexer and the 40-pin FST32X245 16-bit bus switch. Another feature common to each of the four devices is a 4? switch connection between their two ports with a minimal propagation delay of 0.25 ns between inputs and outputs. Pricing begins at $0.95 each /1,000. The FSTU16862 is also available in a TSSOP. For further details, contact FAIRCHILD SEMICONDUCTOR, San Jose, CA. (888) 522-5372.