Switches Enable PCIe 2.0 Switching While Offering Zero Delay
Tue, 05/06/2008 - 12:19pm
Enabling switching PCIe 2.0 data rates at 5.0 Gbps and operating at 1.8, 2.5, or 3.3, the MAX4888A and MAX4889A dual, passive PCIe switches allow multiple PCIe graphics cards to be used in PCs and servers. The MAX4888A (dual single-pole/double-throw- 2 × SPDT) is suited for switching two Rx or Tx equivalent lanes while the MAX4889A quad switch offers twice the capacity, handling four equivalent lanes of PCIe data with the equivalent half lanes used as one source and two destinations or two sources and one destination to minimize the effects of crosstalk. Both feature a single digital-control input (SEL) to switch signal paths designed to minimize power and skew and offer a zero delay switch. Specifications include operation from a single +3.0 to +3.6 V power supply and down to +1.65 V over the extended -40° to +85°C temperature range. The MAX4888A is available in a 3.5 × 5.5 mm, 28-pin TQFN package while the MAX4889A is available in a 3.5 × 9.0 mm, 42-pin TQFN package. Suited for differential-signaling applications where signal levels are centered around ground level, such as DisplayPort.