ESP32-P4 Dev Board: Why IP101GA instead of LAN8720 for Ethernet PHY?

[spacyaldesign]

Hi everyone,

I'm currently diving a bit deeper into the new ESP32-P4 and its peripherals, especially the Ethernet interface.

While doing so, I came across an interesting observation:
On many older ESP32 boards or third-party boards (e.g., the well-known WT32-ETH01), the LAN8720 is very commonly used as the Ethernet PHY.
However, on Espressif's official ESP32-P4-Dev-Board, the IP101GA is used.

Now I'm wondering (and perhaps others in the community are too): Are there specific reasons or known advantages that might have led Espressif to choose the IP101GA for the P4-Dev-Board?

Possible considerations could be:

Performance differences (perhaps in conjunction with the P4)?
Power consumption?
Availability at the time of design?
Cost?
Specific features of the IP101GA that are particularly useful for the P4?
Long-term availability or support from the PHY manufacturer?
Or perhaps simply a strategic decision for diversification?
I know such decisions are often complex. But maybe someone in the community has experience with both PHYs in the context of ESP32/ESP32-P4 or has more detailed information on this. Perhaps Espressif employees also read along and can offer a little insight?

I'd be very interested in your opinions and any knowledge on this! It would certainly help to better understand and optimize designs with the ESP32-P4 and Ethernet.

Best regards

[ondrej]

Hi,

just a quick answer to your question:

1) Espressif has always used IP101 in its Ethernet devboards - https://docs.espressif.com/projects/esp ... t-kit-v1-2

2) LAN8720 always outputs REF RMII CLK at its output even if it's set to reset. It makes board design more complex since GPIO0 is used as bootstrap pin, see https://www.crowdsupply.com/silicogniti ... reset-saga

3) Cost. IP101 is cheaper.