All Questions
Tagged with rs485 differential
19
questions
0
votes
2
answers
84
views
What is SN75176 receiver pin drive current?
I am poor at understanding what datasheet symbols denote. Please help me decode what might be the drive current of receiver logic pin.
Here is the link to datasheet: https://www.ti.com/lit/ds/symlink/...
- 399
0
votes
1
answer
726
views
Is this a legitimate RS485 wave shape?
I'm having issues but first of all I need to verify the other end of the communication line… there is a Moxa TCC-100 RS232-RS485 converter attached to the bus and I see this weird signal on the bus ...
- 8,536
1
vote
2
answers
2k
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RS-485 Network Topology with Backbone and Daisy-Chain Stubs [closed]
I am designing a RS-485 network and would like to know whether the configuration below would work. The transceiver I am using is the Maxim MAX485, with the master ad slaves hardwired to always ...
- 73
-1
votes
1
answer
257
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Micro USB and RS485 Compatibility
I am looking into understanding micro usb better and seem to be missing something apparently obvious different about the difference between micro usb and rs485.
From looking online like here, the ...
- 111
6
votes
8
answers
2k
views
How does the current of RS485 signals return from the receiver to the sender?
I am planning a system consisting of 1 master device which is connected to 19 slave devices using RS485 transceivers. Also, all devices are powered by 1 PSU. A simplified schematic is shown below.
As ...
- 285
8
votes
4
answers
3k
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Why common-mode choke on differential-signal serial lines?
I have 2 questions:
Why using a common-mode choke on serial communication lines (like CAN, RS485) if the signal is differential? Wouldn't the common-mode noise simply be cancelled in the receiver?
I ...
- 83
1
vote
2
answers
2k
views
Differential Signaling and RS485 difference?
I am trying to wrap my head around the difference between differential signaling (mainly LVDS and LvPECL) and RS-485.
All seem like differential signaling for serial communications.
From the TI Page, ...
- 111
1
vote
0
answers
474
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MAX487 can transmit but won't receive
I am trying to use a MAX487 chip to convert a regular UART signal to half-duplex RS485 signal and vice versa. I am using Atmega328PB as my micro controller. My circuit has no problem with transmission,...
- 57
1
vote
1
answer
663
views
RS485 Eye diagram - does it look good?
I got a new diff probe, I am trying it out on RS485. I'm triggering on the rising edge. The RS485 is running at 25Mhz.
Does the eye diagram look good?
Could I double the speed (50MHz) and be ok? (...
- 84.9k
1
vote
1
answer
1k
views
To Fail-Safe or not Fail-Safe on RS485/422 Transceiver
I'm stuck on a PCB design issue.
I'm designing a new PCB (Daughter board) that will plug (via DB15-F to DB15-M) onto another PCB (existing Mother board) and the design intent is to take (from the ...
- 481
4
votes
3
answers
5k
views
RS485 termination
What is the recommended way for termination RS485?
I read about couple of options to do this. If I don't want to do dissipate extra power, can I just put 120 Ohm resistor?
I saw the follow ...
- 91
0
votes
2
answers
894
views
LIN to RS485 and back to LIN
I am currently communicating between two microcontrollers using a single pin and the LIN protocol over a short distance of 0.2m. Now I would like to extend the distance up to 5m by differentially ...
- 707
1
vote
1
answer
995
views
RS485 Waveform while Receiving Data
I was testing the RS485 Circuit, below is my circuit and I connect J5 to my PC using another RS485 to USB converter. In PC through Modscan software I was monitoring the polling and response, a twisted ...
- 687
0
votes
2
answers
1k
views
Differential signal isolation
In differential signal circuits (specifically, RS-485), there is usually an isolation between the signal processing / generation stage (eg, microprocessor) and the line driver chip (something like a ...
- 127
1
vote
1
answer
833
views
TTL output levels on SN75176 transceivier
I have a system that communicates between two subsystems over a distance with UART. The UART signals are converted to RS485 by using the SN75176 differential bus transceiver. A microcontroller on one ...
- 665