Thank you so much for excellent videos, I am sharing with my team to get insight on latest trends

@circuitimage

2 жыл бұрын

You're welcome and thanks for sharing.

excellent video, thank you, you are best

@circuitimage

2 жыл бұрын

You're welcome and thanks for sharing.

You are the best.

@circuitimage

2 ай бұрын

Hi layt01, thank you for the kind words, and nice to meet you. :)

Hi Chen, I wonder if you can talk about "why PAM3" in the future? Some specs such as USB4 Gen4 and GDDR7 rather choose PAM3 instead of PAM4, what do you think from the technical point of view?

@circuitimage

Жыл бұрын

Hi, aaaaa, nice to meet you, and thank you for this excellent question. You can think about the PAM3 being somewhere between the PAM4 & PAM4 in terms of channel loss and design complexity. Since the data rate was < 40Gbps, the channel loss was not big enough to trade the 9dB SNR, but PM3 is good to trade the 6dB SNR by paying the power overhead.

@aaaaa-yv1zr

Жыл бұрын

@@circuitimage Hi Chen, thank you very much for the explanation!

@circuitimage

Жыл бұрын

@@aaaaa-yv1zr You are very welcome. I'm looking forward to seeing your excellent feedback in the future. :)

Thank you. About TX FFE in PAM4, does pre and post apply to bits or to symbols?

@circuitimage

5 ай бұрын

Hi Shadi, You're very welcome. Thank you for the great question. It's a two-bits DAC (ditigal-anaglog conversion), and one for the MSB and the other for the LSB. Then you could do the FFE as the NRZ in each MSB & LSB path saparately. I hope it's clear. If not, I may add one more circuit image video to describe to help everyone understand it easily. Thanks, CC

I learned a lot. Thx

@circuitimage

2 жыл бұрын

You're welcome.

Thank you Chen

@circuitimage

Жыл бұрын

Always welcome

Hi Cc，in5:33，why Insertion loss>9.5dB， VrxEQ_P4>VRXeq_NRZ？the bigger swing of NRZ why through the same loss but have the smaller swing？I can't understand it，could you explain it detailly？except your reply，Best regards,mcgao

@circuitimage

Жыл бұрын

@mengchuan thanks for your feedback. That’s the insertion loss differences (delta L) around 4:30. If both insertion loss differences of NRZ and PAM4 is 15dB. Then PAM4 degrades 3dB and NRZ degrades 18dB, so the eye height of PAM4 is bigger than the NRZ.

@mengchuangao4968

Жыл бұрын

@@circuitimage Hi CC，Got it，Thanks for your explanation！

@circuitimage

Жыл бұрын

@mengchuan You're very welcome.

@circuitimage

Жыл бұрын

@@mengchuangao4968 Sure. Let me know if you have any addition questions :)

@mengchuangao4968

Жыл бұрын

@@circuitimage Thanks and I will continue study your video😀

Are you from Taiwan?

@circuitimage

Жыл бұрын

Yes, I am.

@aaaaa-yv1zr

Жыл бұрын

@@circuitimage 聽你的英文口音確實很像台灣人XD 你是做SERDES的工程師嗎? 好奇為什麼會開這麼冷門主題的頻道(不過我有興趣)

@circuitimage

Жыл бұрын

@@aaaaa-yv1zr Thanks for asking and curious. Yes, I mainly work on SerDes. Since I like it, I would be happy to share what I know even though not many people care or watch the circuit design concepts of SerDes. :)

@aaaaa-yv1zr

Жыл бұрын

@@circuitimage Thank you so much for sharing!!!