Diodes introduces four-port expander

     Diodes Corporation introduces the PI7C1401 four-port extender. The PI7C1401 is an affordable low-speed signal management and I2C aggregation solution for advanced embedded systems with multiple high-speed interfaces. The PI7C1401 is suitable for any application with multiple high-speed transceivers, including standard SFP (small package pluggable transceivers), two-port SFP (DSFP), and four-port SFP (QSFP), such as baseband units, routers, and switters in devices such as telecommunications, networking, and data centers.

     In general, each transceiver requires a dedicated control channel to connect to the host, and this architecture is usually implemented using low-speed signal pins and low-speed communication protocols such as I2C. As systems become more complex, the demands on transceivers increase, and the load on the host controller becomes heavier in order to support a large increase in I2C interfaces and other low-speed signal pins.

     The PI7C1401 aggregates four low-speed ports into a single channel and, combined with multiple four-port extenders, enables the host processor to control up to 56 transceivers through a single I2C/SPI interface. With this design, the host processor or FPGA can significantly reduce the number of pins needed to control high-speed transceivers, simplifying PCB configuration and reducing overall bill of materials (BoM) costs.

     The I2C interface supports 1MHz fast mode, allowing up to 14 PI7C1401 devices to share a single interface. These devices use a Daisy-Chaining mode to connect control pins and automatically set their respective addresses. The SPI mode supports bus speeds of up to 33MHz, allowing an unlimited number of PI7C1401 devices to share a single SPI interface, improving work efficiency. In addition to port aggregation, the PI7C1401 offers a variety of utility features, including four User-Programmable GPIOs and two dedicated outputs for driver status leds.

     The PI7C1401 also supports automatic prefetching of user-defined critical data from modules, customizable data-driven interrupts, high-load read/write I2C/SPI interfaces, and broadcast mode that can write to all ports simultaneously. These features significantly improve the port control efficiency of the PI7C1401 to meet the demanding requirements of high performance applications.

     In addition, the PI7C1401 four-port aggregator supports host independent I/O voltages from 1.8V to 3.3V. The aggregator is in a 56-ZF (TQFN) package of 5mm x 11mm, with a pin spacing of only 0.5mm, and is attached to the bottom of the PCB in a surface-adhesive manner and is close to the physical interface.