LAN data transfer speeds

Question

Hello experts! I would appreciate your answers to the following questions! I found information on the Wiznet website that the w5500 chip supports LAN data transfer speeds of 15Mbps. Is this speed divided between 8 sockets and less than 2Mbps per socket if all 8 simultaneously receive and transmit data? Why the PMODE configuration - 1xx 100M and fast SPI 80Mbps, if the limit is 15Mbps? Moreover, the chip heats up to 55C at high speed (whose chip is cold?). Should the chip heat up to such a temperature at maximum speeds without a heat sink? I need a data transfer speed of about 100Mbps, should I consider the w5300 chip for this?

Eugeny · Answer

spontomdela: fast SPI 80Mbps, if the limit is 15Mbps Datasheet says The minimum guaranteed speed of the SCLK is 33.3 MHz which was tested and measured with the stable waveform I suspect there’s mistake, and 33.3 is maximal guaranteed frequency, not minimal. And the bottleneck may not be in the LAN speed, the bottleneck is in SPI interface and socket management. Max SPI speed is achieved in VDM mode, but before doing it you must read several registers making several requests (which may also be optimized). And yes, W5500 (and other chips of this family) heats because it has PHY drivers inside.

spontomdela · Answer

I work with the W5500 chip at a speed of 60Mbps via the SPI interface, no data loss. Even if only one socket is active, will I be limited to 15Mbps?