The OXPCIe200 PCI Express (PCIe) bridge links a 1x PCI Express host to a pair of USB host interfaces or one USB host interface and an SPI/SRAM interface (see the figure). The bridge also provides access to a serial port and eight generalpurpose I/Os (GPIOs).
The bridge’s dual-USB mode provides one high-speed and one full-speed USB 2.0 host interface. The high-speed interface has a built-in physical layer (PHY). The second requires an external PHY. DMA support is available for all serial interfaces.
A typical application includes a dual- USB expansion card link to USB hard drives. It can also provide access to a range of interfaces that may not be included in the host system. PLX Technology offers bridges that have parallel ports and local bus interfaces as well.
The 3.3-V OXPCIe200 comes in a 9- by 9-mm, 156-ball thin-array plastic package (TAPP). A reference design kit comes on a PC-style PCI Express x1 board. Windows and Linux device drivers are available for the serial port and serial peripheral interfaces (SPIs). Native operating-system (OS) drivers are used with the USB ports. Chip pricing starts at $7.95.