rtl8156+vl822+fe2.1 (full verification completed)

Description: Upgrade to RTL8156 2.5G USB3 network card;
test env: z77+i5_2550k; Gigabit router;
 
This solution supports rtl8156B and rtl8156BS;
S version is actually supply, with built-in SW 3.3V and SW 0.95V, but its SW needs to add inductor, which is not as convenient as my LDO;
S version PIN_5 is defined as: high level turns on the built-in SW, low level does not use the built-in SW;
non-S version PIN_5 is defined as outputting a high level after receiving 3.3V power supply to control the EN pin of the SW/LDO chip to turn on the 0.95V power supply;
the power supply sequence must be 3.3V -> 0.95V, my processing method is 3.3V -> 1KV diode step-down -> LDO output 0.95V -> a bunch of C for delay, so that PIN_5 can be directly pulled down without flying far, and it is compatible with the S version;
 
 
 
 
 
# rtl8156 verification (since the router is only 1G, 2.5G speed cannot be verified):
 
 
 
 
 
 
 
# vl822 verification:
 
 
 
# fe2.1 verification:
 
 
# Experience: Developing this rtl8156 2.5G USB3 network card is really full of pits and pits. This pit has nothing to do with the difficulty. So far, Baidu and G can't find the schematic diagram and complete datasheet of 8156. This has been opened for the first time; there
 
is no complete DATASHEET, PCB and schematic diagram on the Internet. At the beginning of that month, I went to the realtek official website and sent an email to the mainland agent to get a datasheet pdf to see the PIN definition. Unfortunately, the agent is just a decoration or no reply;
 
I sent it to realtek technical support and they said that I had to contact the agent to sign an NDA for confidentiality before I could get the datasheet pdf. However, the technical support MS/MR Gu was still very good. He didn't give me the datasheet pdf, but gave me the public version map; there is rtl8125 of the same generation, which is also 2.5G, pci-e, and LiChuang has a PDF. Then compare the PIN definition, For unclear definitions, you can just use the method of retaining the space for flying wires to draw;
 
then start drawing, I saw 3 unofficial ones in the standard version of the package, all the same, imported them into the professional version and spent 1 hour to draw, and drew 2 versions, which were nothing more than a DCDC and an LDO for power supply, and then you know what I got for free, I went to buy RTL8156, and then it happened to be the Mid-Autumn Festival when LiChuang was on holiday, so the board arrived on the 15th;
 
when the board arrived, I soldered the QFN last, soldered the parts, and soldered the VL822, and found that the pins of the RTL8156 were not aligned, so I took a ruler to measure that the RTL8156 was QFN56 6*6; the 3 RTL8156 libraries in the standard version were QFN56 7*7, which was obviously a rip-off, but fortunately I didn't feel bad about getting it for free, But I have used up all the freebies this month;
 
I have not received any coupons for the promotion, so I have no choice but to spend 20 yuan to make a board. I have been soldering it from today to today, and it is OK after testing. I won’t waste it anymore;
 
# update:
2022/09/21: Corrected the video. When I recorded it last night, the SSD had not been turned on for too long, and it was stuck in the cold data processing inside; it was powered on overnight and it was normal when I woke up today;