Questions tagged [rj45]
For questions about Registered Jack 45, an 8 position 8 contact (8P8C) modular connector commonly associated with Ethernet and category 5 (Cat 5) cables. Consider using in conjunction with associated tags "connector", "ethernet", "cat5", "cables", etc., if applicable.
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Identify board found on eletronic diposal
I have found this board on a electronic disposal point on my college.
I'm not sure if it's working, but i'm very curious about it.
It has a display, 4 buttons(one is damaged), some leds, a PIC18F448T-...
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1
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Why are green pair (or orange pair) wires not adjacent in RJ45 connectors?
For the sake of the discussion, let's talk about T-568B, but this applies to T-568A as well.
I've searched a bit for why the green cables are not adjacent, and the answer was that this reduces ...
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Which is preferred over differential pairs: trombones or sawtooths?
I have been told that trombones are much better to use than sawtooths, even if sawtooths may be prefered in some certians scenarios.
Here I have added trombones to the differential pairs. If I had ...
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The pin configuration of an RJ45 network connector Pulse J0G-0001NL
I have a few questions about whether I have pulled the right one for this RJ45 connector.
It's a Pulse J0G-0001NL and the pin configuration is below.
But note that if you look at the pattern, you ...
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How can I configure RealTek RTL8211F for 100Base-T?
Introduction
I'm planning to use RealTek RTL8211F Ethernet PHY.
I have an example schematic.
Problem
The problem here is that the RJ45 Ethernet connector 48F-01GYDXNL is very difficult to get and I'm ...
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Ethernet cable testing
I'm working on designing a device to identify ethernet cables after they have been installed. I've designed a circuit that will send a DC high signal via one wire and then returned over the remaining ...
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1
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160
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Wiznet W5100 and Realtek RTL8363NB-VB-CG board issue
I've built a PCB connecting one of the ports of the RTL8363NB-VB-CG to the W5100 mimicking a ethernet cable on board, I used a RP2040 a Wiznet 5100S-L and the Realtek RTL8363NB-VB-CG.The problem that ...
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Ebyte NS1 Design question
I am working on a new design dev board base on stm32h750 and Ebyte NS1 Ethernet Module .
Ebyte give 2 design in data sheet .
1 one with a filter HR641680E
2 with a RJ45 build in 2KV electromagnetic ...
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Ethernet with incorrect pinout still makes link?
I designed a board recently that accidentally had an incorrect pinout on the RJ45 jack for Ethernet. Instead of following TIA568, I instead routed it straight-through:
Oh well, simple mistake, ...
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Harmonics of Ethernet (100MBps) MLT-3 signals [closed]
I have EMC Issue (Radiation) as attached..where at some frequencies the emission levels are exceeding the limits..
I use 36V power and Ethernet (MLT3) for communication.
These failing frequencies are ...
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2
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Ethernet Magnetics Polarity Swapping
Can I on the same pair (for Example A) to swap polarity on opposite side of transformer/magnetics?
Update 1: Currently i use cross-over method to make lanes shorted and more easy to layout.
Update 2:...
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2
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Lifting Pins on SMT RJ45 Connector
I'm running into an issue with a specific RJ45 SMT connector where the I'm getting at least 1 pin lifting on >50% of the boards that run through our reflow oven. The rest of the components on the ...
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Useing a PoE RJ45 ICM Magnetics but not using it for PoE?
I plan on using the Bel G27-122T-015 (PoE ICM RJ45) but I don't need it for PoE. Can I just leave these pins unconnected? The ICM already has an internal Bob Smith termination.
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Do I need to keep twisted pair ethernet wires consistent down the entire cable?
I have an ethernet cable that is hooked up to a 20 foot long 24 AWG twisted pair cable. The twisted pairs are not twisted to the same wires like in the ethernet cable. Would this be a problem? I ...
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How do I connect an Ethernet Jack to LAN8720
I'm looking for a way to correctly connect an RJ45 socket to a LAN8720 chip, but cannot seem to find much information in the datasheets. Here is the datasheet for the LAN8720.
And here is a data ...
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Hot-plugging current - TVS and ethernet
My question is based on this question over here
In one of the comments, it is mentioned,
"TVS on the media side would seem to invite short-circuit currents on hot-plugging. Putting it behind the ...
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Easiest way to IP68 waterproof RJ45 cables/ports/splitting?
Consider the following simple daisy-chain arrangement:
Protocol is MODBUS. Electrical standard is RS485.
Cables also carry 12v DC power (Power over Ethernet) to the sensors.
All cables are CAT5e ...
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Expected impedance across TX pair and RX pair on a functional RJ45 port
I'm using a sensor that has ethernet output. This new sensor is a replacement of yet another same sensor that seemed to have short-circuit like situation between its RX+/- pins.
After connecting the ...
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Direct Ethernet link between Raspberry CM4 and Jetson Orin Nano
I need to have high speed communication between Raspberry CM4 and Jetson Orin Nano modules on the same PCB.
My question is: can I route them through Ethernet directly without the need for an isolator ...
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RJ45 Connector - Capacitors
I need an STM32F4 to communicate through LAN.
An electronics technician provided a schematic (Version 1), of which I'm only showing the relevant part.
I did my own research on the Internet and in the ...
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161
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Connect and disconnect Ethernet line
I need an IC to connect and disconnect the network cable line (TX+ and TX- lines to connect/disconnect)
Can I use an analog switch IC?
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Ethernet transformer TD/TX sides
I’m curious as to the side the TD and TX side go to on an Ethernet transformer.
I have drawn this schematic below and the datasheet for the Ethernet transformer chip is attached as well but I’m not ...
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How to connect USB-to-RS485 adapter to RS485-RJ45 input of an LFP battery BMS? [closed]
I have Victron Multi 48/5000 connected to Cerbo GX. Works fine.
Now I need to connect Cerbo GX to the LFP battery, to RS485 (because no CAN input).
...
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0
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219
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Shielding issues with RJ45 connectors
I've been dealing with a pretty nasty radiated emissions problem at work and I've pretty well exhausted any list of potential solutions/mitigation tactics to resolve this given the design constraints. ...
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1
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Why are non-conductive circuits designed on PCB？
This is the PCB of the network communication industry.
What I know now is that after adding these redundant non-conductive circuits, the performance is improved from Cat3 to CAT5e.
I really want to ...
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Raspberry Pi ethernet socket type T-568A or T-568B
I'm using an rpi model B rev 2 as a wifi access point and need to run a long cat6 ethernet cable to its location from the router. It works fine with an off the shelf ethernet cable but I need to make ...
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RJ45 termination in fast ethernet
I am working with fast Ethernet. My question is that we are using only two pairs in 100 Mbps.
How will I terminate pin 4 and 5 and pin 7 and 8?
Can I separately terminate magnetic center tap with a 75 ...
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2
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218
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Ethernet RJ45 Connector?
I have plenty of HR911130A in stock because they are small and directly compatible with Raspberry PI.
For another project, the reference design recommends the 7498010210A connector, which is slightly ...
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Can I use an RJ45 plug designed for UTP with STP wire?
I have a non-standard application (model railroad) where I am planning to use CAT6 wiring between a custom made circuit board and a display panel. The circuit board will have RJ45 ports (using ...
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234
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EtherCAT Communication Testing
I am working on a device that uses EtherCAT. On one side, I have the standard EtherCAT Connector - an RJ45. On the other side, I would like to experiment with different connectors. For starters, I ...
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2
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842
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Understanding 24 V PoE mode B magjack connections
Having just realised I have screwed up my board by stupidly swapping pins 4 & 5 on the magjack output, I have realised I don't properly understand the PoE power pins on the magjack. I wonder if ...
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RJ45 PCB Design Transformer & MagJack
Designing a PCB board that supports RJ45 using W5500, yet I'm confused with two issues:
Magnetic jack: Is it required?
Is transformer required if Magnetic jack is used? Or are they unrelated?
By ...
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Can I punch down regular hookup wire in an RJ45 Keystone Jack?
I'm planning to use CAT5e cable for a model railroad application and on the far end of the wire I am looking to use a keystone jack. My question is whether or not regular hookup wire can be punched ...
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3
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W5500 ethernet controller link problem
My design includes an STM32, a W5500 and this RJ45 connector which has a 1000pF/2kV capacitor.
The problem is that when I connect a cable to the RJ45, the orange LED always blinks. This indicates no ...
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9 wires in a CAT5e cable?
I just cut open a CAT5e cable since I wanted it for a project which required several twisted shielded pair cables. To my surprise there were 9 wires with isolation? I was under the impression that ...
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Interfacing RJ45 to 3 pin RMII and bidirectionality
I am trying to add an Ethernet interface to a dev board (This board specifically).
From looking at the schematics, I see that it has a 3 pin PHY input (GND, TRX+, and TRX-). From my understanding, a ...
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Ethernet RJ45 M-F cable (socket <-> plug)
During renovation I've asked the electrician to use two long patch cables originally running from my router to create RJ45 sockets with the intent to later connect the router to the socket using a ...
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Not getting linkup on Ethernet with ESP32 MCU
I have an issue regarding ethernet with an ESP32. I have designed a hardware with an ESP32 and DP83848 phy for ethernet connection.
The problem is I don't get link up from phy.
I am running the ESP32 ...
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0
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What to do with unused pins on a 1000BaseT RJMAG jack
Trying to figure out what to do with the unused wires heading into the magnetics on an RJMG2330A1610ER Ethernet/USB jack. Due to the craziness in manufacturing in the world I am forced to find a ...
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Ethernet Surge Protector Speed
I've been investing in some new surge protectors lately – a fraught process at best given the difficulties of comparing model and brand quality. Things were even trickier when looking into ethernet (...
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How to connect Ethernet Magnetic/RJ45
I am connecting up my PHY to an RJ45 with magnetics and was wondering what I do with some pins on it.
Here is the circuit for the Rj45 w/ magnetics.
My questions are:
do I connect pin 10 to the ...
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Can I convert my dozens of laptop adapters into universal ones by using RJ-11 or RJ-45 connections?
I have accumulated dozens of laptop (and other) power bricks over the years. Some of them belong to a corresponding laptop or device, others just haven't been thrown away yet.
I'm trying to make them ...
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protect RS485 from PoE
I have a board with two RJ45 connectors.
One is used for an Ethernet port and the other one is for a RS485.
The Ethernet is for Power over Ethernet.
What are some suggestions to protect the RS485 port ...
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Difference between the two Ethernet magnetic topologies
Background
Hello, I'm building up a PCB for a PoE module based on Microchip LAN8720 IC. The recommended schematic is shown in the following figure.
I built up a prototype based on the Waveshare ...
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Center Tap (CT) pins in RJ-45 Connector
I'm not an Ethernet connector expert. I was wondering what are the CT pins in RJ-45 connector are used for.
From a search in https://www.edaboard.com/ I found this interesting answer from a user ...
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How to connect interfaces' shields?
I am designing a new PCB board these days, and I am confused about how to connect interfaces' shields. The interfaces on the board include USB, RJ45 and D-SUB, should them be connected directly to ...
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Transmitting I2S over 6ft
I've been looking at audio ADCs with most rated at 192Ksps with 24 bit audio. Typically the output is in I2S, but I understand that the signal is not intended to go far. I understand that HDMI can ...
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Manually Use LEDs on RJ45 Connector [closed]
I am using RJ45 connectors(2-406549-1) with built in LEDs, to transmit SPI lines for a microcontroller project(I needed CAT 6 cables for twisted data/ground pairs).
I'd like to use those built in LEDs ...
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DMX over RJ45 daisychain extra pins?
Im building a DMX controller that uses RJ45. (Controller as in lights are connected to it) I will obviously have 2 RJ45 jacks for daisy-chaining. What I was wondering is, I've seen that multiple ...
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10Gb link data transfer between FPGA && PC [closed]
I'm trying to transfer data from 10Gb ETH subsystem of FPGA to 10GB ETH card of PC. SFP, RJ45 and ETH cable comprise of this data transfer pipeline. The RTL code is ready for testing and I'm looking ...
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