Questions tagged [lan8720]
The lan8720 tag has no usage guidance.
9
questions
1
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1
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LAN8720 MDC (SMI Clock) and/or ringing issue
I had always difficult times with designs having LAN8720 device on it. It behaves differently with each design (this is understandable and even I carefully design it according to the design ...
- 283
1
vote
1
answer
204
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LAN8720A - PoE Protection
I will go straight to my question.
I have currently a PoE PD using LAN8720A PHY,
i follow almost all manufacturer recommendations on PCB layout and schematics, anyways i have dead LAN8720A straight ...
- 23
0
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1
answer
238
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STM32F407 + LAN8720 status LED keeps blinking fast, error?
I made a custom board around STM32F407 MCU that is connected with a PHY Board with a LAN8720 IC via RMII. I also have connected an 2.42' OLED Display based on SSD1309.
I notice when I turn on the OLED ...
- 189
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1
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1k
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LAN8720 50Mhz clock: 33R termination/adaptation resistors
I'm trying to understand the function of these three 33R ohms resistors.
The full schematic is here: Schematic
I can understand the objective of R14 and R12: Split the clock and adapting it, but what ...
- 23
1
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1
answer
779
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Problem with ferrite bead - reduces power supply voltage
I built my own board with a LAN8720 chip but I can't get it to work. I found out that the ferrite bead I used only outputs ~1.4V from 3.3V input, which is way too low.
I used some guidelines and other ...
- 311
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1
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755
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Crystal Oscillator for STM32F407 with LAN8720
I'm planning to build a custom board with STM32F407 chip for a system where I also need Ethernet connectivity.
I'm planning to connect this board to a LAN8720 with breakout board from Smart ...
- 189
0
votes
1
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110
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Identification of Pin1 on LAN8720A 24SQFN package
can anybody help me identify which is pin 1 please? - which corner and side is pin 1?
I find the data sheet and the actual picture confusing between the Datasheet
and the device
- 59
0
votes
2
answers
451
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Inverting REFCLOCK of Ethernet PHY
A few years ago I had to design a board that uses the NXP LPC1769 MCU and had Ethernet connectivity. I was in need of a PHY chip and the LAN8720 was choosen.
During design however, I noticed that NXP ...
- 1,800
12
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3
answers
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STM32F407 + LAN8720A + lwIP + FreeRTOS = No received Ethernet frames
I'm trying to bring up a PCB that uses an STM32F407 and LAN8720A Ethernet PHY, and I can't seem to receive any Ethernet frames — even though I have no problem transmitting frames.
Hardware setup
I ...
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