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Questions tagged [rj45]

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0
votes
2answers
70 views

Can you replace a RJ45 connector with smaller connector?

I'm designing a small board that needs an ethernet connection. However, the RJ45 jack takes considerable space. I would like to reduce the footprint of the connector to safe some space. Would it be ...
2
votes
3answers
84 views

Power small microcontroller from motherboard RJ45 ethernet port

I'm wondering if it's possible to power a microcontroller (e.g. ATmega328) from a Ethernet RJ45 motherboard port. Unlike USB, there is no power line, all pins/lines seem to be data only. I am ...
0
votes
4answers
91 views

What can happen if 24vdc is applied to an Ethernet port?

We have a device with two RJ45 ports. One of these ports is for receiving 24vdc on pins 7(-) and 8(+) to power the device. The other RJ45 port is an Ethernet connection. The ports are of course ...
0
votes
0answers
41 views

Connectors in outdoor enviroment

I designed multiple modules which have to be connected in an outdoor environment but are located in rainproof casings. These modules don't get wet from direct weather and have no direct exposure to UV ...
0
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0answers
19 views

ENC28J60 - is this connection correct

Just wondering if this is correct. I never used to design anything using this chip.
0
votes
1answer
55 views

Is it possible to use the same RJ-45 connector?

Given that the wires are connected to the pins and crimped with a crimp tool; is it possible to "un-crimp" the wires such that they can be unattached from the RJ-45 connector? Whereafter the connector ...
0
votes
2answers
59 views

Can I run DC voltage through RJ45 Connector with Magnetics?

I am designing a PoE (Power over Ethernet) application. My question is can I run 48V DC Voltage through a standard RJ45 Jack WITH Magnetics? or do I need one WITHOUT magnetics? I am planning to use ...
0
votes
3answers
210 views

How to route Ethernet PCB ? [closed]

I am new to PCB routing. In one of my projects, I need to be able to exchange data between nano-computers (https://www.variscite.com/wp-content/uploads/2018/01/DART-6UL_DART-6UL-5G_Datasheet.pdf) ...
1
vote
2answers
75 views

Divide RS-485 Simply without switch

I have an RS-485 input / output from a solar charge controller (SCC) and would like to read the output in two locations, while maintaining its input from one, or hopefully both of those locations (see ...
2
votes
1answer
342 views

DHT22 bad readings on long rj45 cable

Duplicate of https://raspberrypi.stackexchange.com/questions/91781/dht22-bad-readings-on-long-cable, I figured there is chances people here have a solution for me. Hi, I'm preparing a setup with a ...
-1
votes
1answer
100 views

USB over RJ45 to USB C [closed]

I am working on an Arcade Stick/Fight Stick enclosure. Internally, the PCB (Brook UFB) runs USB over a standard Ethernet cable, to a Neutrik RJ45 passthrough. I typically then create an RJ45 to USB A ...
2
votes
1answer
92 views

Daisy chaining I2C modules using CAT5 and P82B715

I'm planning to connect several modules over I2C with distances between modules ranging 30-180 cm. I understand that in order to avoid the degradation of the signal due to the capacity of the ...
0
votes
1answer
119 views

MagJack for PoE Powered Device

I am adding Power over Ethernet functionality in my Toradex's System-on-module (Colibri iMX6ULL) based carrier-board design. I ...
3
votes
3answers
249 views

Flooded LAN RJ-45 connector may damage connected router? [closed]

I had an accident in the house and one of the LAN (cat. 6) cables including RJ-45 connector has been flooded. This "flooded" cable, along with other (dry) ones, was connected into a working gigabit ...
0
votes
1answer
94 views

Ident of a 10 contact RJ45 style connector with 8 + 2 contacts

I'm trying to find a plug that will fit into this RJ45 style socket. The top picture shows 8 contacts just as you would expect from a RJ45 8P8C style socket, in fact you can plug a standard ethernet ...
15
votes
4answers
4k views

What is the purpose of two cylindrical holders in RJ45 female connector for PCB

I am a beginner in PCB design. While using sensors for my project I thought it would be a great idea to connect my sensors using RJ-45 connector and in my device, I'm thinking of using a RJ-45 female ...
0
votes
2answers
102 views

How does things work between MODEM and PC on the RJ45 ethernet cable? [closed]

I am a newbie in electronic and i would like to ask why there is Transmitter and Receiver in the RJ45 cable connecting the MODEM and Computer? Which one goes first From Modem --> Receiver Receive ...
1
vote
1answer
197 views

Using Ethernet Cable in Electronics Projects

I'm building a cue light system (think traffic lights for theatre, media and entertainment industries) and I need to connect outstations (the traffic lights) to the control station (Arduino). Each ...
1
vote
0answers
51 views

Connecting WIFI Module to RJ45 pins output of device

Extreme noob questions here. I have a Lantronix XPico 240 wifi module that I need to connect to the rj45 output pins of a device the device pins are clearly marked but I am not sure about which pins ...
1
vote
2answers
443 views

Solder Ethernet directly to board? [duplicate]

I'm building a system based on one of the old Raspberry Pi model B's (yes, first series) into a very small enclosure. I need to run an Ethernet cable from the POE splitter I have in this enclosure to ...
0
votes
0answers
1k views

RJ45 jack with 8 and 10 pin difference

I need to use the next Ethernet interface design which it's got a RJ45 10 pin, the schematic looks like this: (The RJ45 datasheet is: https://katalog.we-online.de/pbs/datasheet/7499111446.pdf) (PHY ...
1
vote
2answers
156 views

RJ45 Type Connector With 10 Lines

What is the name of the connector that is similar to an RJ45 but instead of eight lines, it has ten?
0
votes
1answer
650 views

RJ45 to RS232 With Power [closed]

I'm using a barcode scanner that will dump the coded values over a serial port and need to have power also sent to the barcode scanner over the same cord just like with the cord shown here: ...
0
votes
2answers
111 views

RJ45 Split, one part Ethernet other part telephone.

I have a patch panel and some ports that allow me to patch telephones lines. So, I use this patch panel to give a wired connection to some devices and I also use it to provide a telephone point. The ...
3
votes
1answer
285 views

Splitting a cat 6 cable through wire/cable connectors

There's been a cock-up in the internet wiring at a building I'm helping out at (I'm installing the networking there) and the builder has tried to rectify the situation with a solution I have zero ...
3
votes
1answer
146 views

Correct Ethernet Jack + Magnetics for 100Base-TX

I've been shopping around for Ethernet jacks for use in a personal project. The part specifically states that it's internal PHYs are 100BASE-TX/10BASE-T/Te IEEE 802.3 I understand the basic ...
16
votes
6answers
4k views

Is there a low-cost alternative to RJ45 cables for large number of signals?

We are designing two interface (printed) boards and need to connect them by cables (0.5-1.5m). So we're thinking about which connectors to use. We'd like to use twisted-pairs like in a RJ45 cable. ...
3
votes
3answers
817 views

RJ45 connector on breadboard

For my project which for the next (many) months I want to make it on a breadboard. I ordered RJ45 connectors, but these do not fit on a breadboard. What would be a good way (or is there a way) to ...
2
votes
3answers
255 views

Are RJ45 jack sockets universal regarding CAT-X cables

I've noticed some trade/wholesale websites list CAT-X jack sockets separately as the individual numerical version, i.e., (CAT-3 jack socket). I'm aware CAT is a standard, and RJ45 is the socket ...
1
vote
2answers
363 views

RJ45 dual LED green and yellow operating

Attached is a small section of USB to Ethernet converter design. RJ 45 Connector has one dual LED (see attached) Green and Yellow, backward connected, and drive via the LAN9500 chip pin27. As per ...
2
votes
1answer
82 views

Unshielded RJ45 connectors on SFTP Cat5e

I have "inherited" an old SFTP Cat5e cable connecting the basement of my house to the upper floor. There seems to be a break on some of the wires (6 and 7) so it won't even function at 100mbps. I ...
1
vote
1answer
106 views

Gigabit Ethernet Coupler Design

I'm doing a PCB design which includes a Gigabit Ethernet 'coupler' - i.e coupling from one CAT 5e cable to another via my PCB (see sketch below) My question is, how careful do I need to be with ...
0
votes
1answer
373 views

Using unshielded RJ45 with shielded Cat6 in a server cabinet

I'm about to do cabling in a server rack that consists of two switches and forty 1U servers. Since every server has three ethernet cables attached we'll have around 120 cables in a single rack. Is ...
2
votes
1answer
3k views

standard ethernet pinout for M12 A coded

I would love to follow the most common pinout (I design connector and receptable, but you never know). I find conflicting sources: -RJ45 connector exact same pinout number by number: -A big cable ...
1
vote
2answers
138 views

Detect activity on RJ45

I would like to make a circuit that allows to detect activity on a RJ45 cable (on which Ethernet would be used). When the cable is only connected to a single computer, link test pusles are emitted. ...
1
vote
1answer
146 views

Unidirectional PHY transceiver

I am trying to establish a unidirectional connection over a RJ45 cable (not an optical fiber). I saw in the IEEE 802.3 standard that the clause 66 describe how unidirectionnal chips should work. ...
-1
votes
1answer
274 views

LG TV RS232 Control over rollover cable [closed]

My LG TV can be controlled over a RS232 port! The Problem is that I don't have any serial devices to test it. So my question is, can I do it with a rollover cable(RJ45 <--> D9)? I mean can I ...
2
votes
1answer
218 views

What is the name of this connector on the end of a serial cable (not DB9)?

I just found that a piece of hardware I would like to connect via a serial port uses a non-standard hardware connection. One end is a female DB9 the other is what I think is an "old" telephone ...
0
votes
2answers
332 views

Is there an excuse for a 20ft Cat6 Ethernet cable to have 36μH on all wires?

I was just measuring the inductance of the 20ft (6m) Cat 6 Ethernet cable I just bought. I'm aware that 525 nH/m is what's expected for each wire, so that ought to have been 3.15μH. I've measured ...
0
votes
1answer
873 views

How to connect RJ45 (female) Link LED

I need a bit of help. I have some Jtron RJ45 sockets (do a quick search, for a better picture), and they have LEDs integrated. I want to connect these sockets to a PCB and get the internet in (added ...
0
votes
1answer
754 views

What do pull-up and pull-down resistors do in an ethernet PHY?

I've noticed that most ethernet physical layers (i.e. the interface between the MAC/network and e.g. an RJ45 connector with magnetics) have pull-up or pull-down resistors on the TX and RX lines. For ...
0
votes
3answers
1k views

RJ45 jack to PCB

Everyone, hello! So I'm building a PCB in my head right now, and I just wanted to quickly eliminate a thought I had in my mind. When I add a RJ45 jack connector to my PCB board, there are (depending ...
0
votes
1answer
154 views

Double magnetics for ethernet?

I have a main board with a 10/100 MAC and PHY. This board also includes a discrete magnetics. The board is connected via a suitable high speed board-to-board connector to another board, that contains ...
0
votes
1answer
415 views

Ethernet PoE Magnetics Pin swap

I have the following circuit right now Is it possible to connect PHY_TRXP0 on TD1- and PHY_TRXN0 on TD1+ and taking ETH_MX1_P from MX1- and ETH_MX1_N on MX1+ respectively? Signals on RJ45 will go as ...
2
votes
5answers
1k views

Replacing RJ45 connector with another type connector

I am looking for a replacement for an RJ45 panel mount connector. Can I use any standard connector (picture below) for connecting Ethernet networks? I know about cable impedance matching but I was ...
2
votes
1answer
521 views

Parallel differential signals

I need to send some I2C data through RJ45 cable between Arduinos. One ATMEGA2560 as master and 1-4 328P's as slaves. I've seen some different configurations and I think for my application the solution ...
0
votes
1answer
73 views

Ethernet device voltage protection

I am designing a system with multiple remote devices connected to a central hub, supplying low voltage DC power and RS-422 data. I plan on using RJ45 connectors, and am wondering if ethernet devices ...
4
votes
3answers
3k views

Creating a PCB mount RJ45 male plug

I am wondering on how one could build a male RJ45 connector with PCB Mount. I searched and, as I expected, I did not found any existant connector like this. However, I found this interresting item : ...
3
votes
1answer
968 views

Are there downsides in using cat5 / cat5e cable for USB 3.0 connection?

It's been pointed out many times that USB 2.0 can (more or less) safely be used with cat5/5e cables and connectors, at least as long as these requirements are met: Data pins are on its own twisted ...
0
votes
1answer
84 views

Multiple signals over single RJ-45 cable

I need to set up a Raspberry Pi system with remote storage, but only have access to a single RJ-45 cable. This limitation is so the system may be replaced in the future, without having to change the ...