New answers tagged ethernet
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Accepted
Clock out drive strength - Current
Usually having a variable drive strength allows a chip adjust the strength based on need.
Faster signals need faster edges which can be achieved with stronger drive ability, but it requires more power....
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Meaning of Speed and Duplex pin in the IC
These signals are generated by an external physical layer controller (the PHY) and tell the MAC how fast and what duplex the Ethernet link is in:
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How to find the maximum power dissipation or Thermal resistance (J-A)
Web search results may vary.
It depends greatly on PCB & heatsink design, convection, airflow or enclosed
https://www.datasheetarchive.com/pdf/download.php?id=...
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Accepted
How to find the maximum power dissipation or Thermal resistance (J-A)
See section 7.
The storage temperature is listed as -65 to 150 C. This might mean that Tjmax is 150 C. But there is no guarantee that it will function correctly at that temp.
See note 7-4.
The maximum ...
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What is support for an end-to-end and peer-to-peer transparent clock?
Your quote omits information what it refers to. Here is better quote from the marketing material:
IEEE 1588v2 is supported via the integrated IEEE 1588v2 hardware time stamp unit, which supports end-...
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Why is this 75 ohm resistor present in the Ethernet connector? (10/100Base-TX)
A slightly simpler answer.
Other answers correctly describe this as Bob Smith termination. Here is the patent that describes how it works. Here is an article that throws some scepticism on it.
However,...
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Why is this 75 ohm resistor present in the Ethernet connector? (10/100Base-TX)
It's called Bob Smith termination.
As there are multiple pairs, a pair also forms transmission lines with other pairs and may pick up or radiate EMI. The termination network reduces common mode ...
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Why is this 75 ohm resistor present in the Ethernet connector? (10/100Base-TX)
It's called "Bob Smith termination" and it's for providing a path for common mode EMI. There's ongoing discussion on "which is better 75 ohms vs 52.3 ohms" and "is it even ...
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How to monitor Ethernet packet loss real time on different connections?
You have a small problem: Between the count that you need to put into your packet and that packet actually being sent, other (payload) packets might be sent. You need to give your status packets some ...
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Can I use a 50m network cable to power two 24VAC solenoid valves?
Think of wire as a low-value resistor. The thicker the wire, the less its resistance. The question then becomes "Is adding a resistor to the load going to cause a problem?" The voltage drop ...
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Ethernet connectors shielding/ grounding
IF your housing is plastic,shield connector is useless because ot is not 360 shield. And for the ESD it is better not connect the connector to system ground because it will into it IC ground directly, ...
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Accepted
Ethernet Switch and QoS Support
QoS (Quality of Service) broadly refers to systems which allocate the available data rate among different data streams in some way other than the default. The picture does not represent different ...
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Differential signalling
I'm using a 1000BASE-T Ethernet. In that case, can I split the
ethernet differential signal pairs into 2?
If you mean can you take a differential signal and simultaneously feed it to two other ...
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Splitting of a differential signal
You seem to want to be able to select which of two RJ-45 connectors are connected to an Ethernet PHY. This is a solved problem, analog multiplexer chips that can switch Gigabit Ethernet do exist.
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Splitting of a differential signal
No, you can't connect RGMII signals to two different RJ-45 connectors, or directly to one at all.
The MII interface (RGMII is a faster, fewer signal variant) is used between the MAC (most often a ...
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Splitting of a differential signal
In general, we cannot split any differential signal and use it on two outputs.
If we are careful, we can split a differential signal and measure the two lines individually as single ended signals.
A ...
1
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Accepted
KSZ8081 PHY address configuration
The answer to your question is, yes, pulling address config pins low will result the PHY address being 0.
Datasheet says it is configurable to any value between 0 and 7.
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Accepted
Ethernet Switch configuration mode
The answer is on page 44:
4.5.2 MAC INTERFACE CLOCKS
The MII interface is clocked asymmetrically, with the PHY device driving both the RX_CLKx receive clock and the TX_- CLKx transmit clock to the ...
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Effect of Ethernet PHY interface on the speed of Ethernet
The ethernet controller will exchange packets through a 10Mbit/s or a 100Mbit/s link. Those packets are sent from or stored into internal memory in the controller, at full speed. The rest is up to you,...
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Effect of Ethernet PHY interface on the speed of Ethernet
The chip can connect at 10 Mbps and 100 Mbps Ethernet link speeds, and it has a maximum SPI bus speed of 40 MHz.
So yes, even if it can communicate with 100 Mbps link speed, it won't achieve 100 Mbps ...
15
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Accepted
Effect of Ethernet PHY interface on the speed of Ethernet
The Ethernet controller datasheet you link claims 10/100 Mbit/s speeds, not Gbit/s speeds.
The controller is capable of negotiating with other 10BASE-T or 100BASE-TX interfaces on the network, and of ...
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Effect of Ethernet PHY interface on the speed of Ethernet
Ethernet link speeds range from 10 Mbit/s to 400 Gbit/s currently. Generally, each Ethernet frame must be transmitted atomically, without any pauses.
For low-speed devices, that mandates decoupling ...
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