The matching device placed at the end of a trace that is acting as a transmission line. This termination prevent reflections from the end of the line and ensures a complete transfer of energy in the waveform into the receiving unit.
5
votes
2answers
134 views
CAN Transmission and termination resistors
I have been trying to set up a CAN network using PIC18F25K80 microcontrollers and an MCP2551 to communicate between them. Can I use two simple wires as a CAN bus by just connecting the CANL, CANH of ...
0
votes
1answer
102 views
Simulation software to terminate planar waveguides by geometry and material choice?
There are a lot of electromagnetics software modeling suites out there (HFSS, CST Microwave, Sonnet some I've heard of).
I want to terminate a coplanar GS or GSG waveguide with 50 ohm. I know that ...
3
votes
1answer
269 views
How to terminate a coplanar waveguide with 50 ohm load?
So I want to structure a coplanar waveguide by lithography, VNA - coaxial - picoprobe - coplanar waveguide transition to measure impedance of the waveguide. As signal and ground lines are on one ...
3
votes
1answer
112 views
Coax cable with CAN bus
I got some Microchip CAN transceivers and some Stellaris Launchpads from TI. I would like to learn how CAN works. It looks very nice for what I want to do (one controller per room, controls lights, ...
7
votes
2answers
1k views
Why does the CAN bus use a 120 ohm resistor as the terminating resistor and not any other value?
I know the reasons for using terminating resistors on a CAN bus and how important it is.
But why 120 ohm? How did this value come up? Is there any specific reason to use 120 ohm?
5
votes
3answers
267 views
Is there a preferred placement of termination resistor for a differential clock line?
Looking at a reference design board from Xilinx, we noticed the placement of the termination resistor for a differential clock line (~300 MHz):
The resistor is placed not at the closest possible ...
0
votes
0answers
28 views
Termination resistor [duplicate]
Possible Duplicate:
How termination resistors work; what happens if I use lower values?
How the termination resistor in reducing the reflection signal in term of theory? what is the ...
0
votes
1answer
105 views
determine the value of termination resistor
How to determine the value of the termination resistor ? the termination resistor is used to reduce the reflection of the signals and also have to match with the transmission impedance? How am I going ...
12
votes
2answers
934 views
Termination resistors: are they needed?
For a project I'm designing, I'm using an IS42s32800 (TSOP) SDRAM with an LPC1788 (QFP) microcontroller. On the PCB I have 4 layers with a ground plane right below the top signal layer and a VDD plane ...
5
votes
3answers
2k views
SPI Bus Termination Considerations
So, in my previous question I asked about using the SPI bus over short distance for board to board communication. I was recommended to try termination resistors. I placed a resistor close to the ...
2
votes
2answers
434 views
At what cable lengths are termination resistors required for RS-485 networks?
I've noticed my experiments in the lab with RS-485 work fine with fairly short cables, but termination resistors are needed for true installations. Is their presence or absence a function of the ...
2
votes
2answers
274 views
How do I use directional couplers on a differential signal?
I understand how a directional coupler can be used to measure signals travelling in one direction on a wire. What I don't understand is exactly how this would work on a differential signal, E.G. LVDS ...
3
votes
2answers
236 views
Why does the ISDN S0-Bus require terminating resistors?
It is a well-known fact that ISDN S0-Bus must be terminated with 100ohm resistors to match the transmission line. This is the case even for everyday household installation with cable runs shorter than ...
2
votes
1answer
259 views
Terminating Transmission Lines with a Resistor
I have a large, but slow, SPI bus comprising of 8 devices. The frequency of operation is 2 MHz. As I understand, I need to ensure that the bus lines are properly terminated or reflections may cause ...
10
votes
3answers
435 views
Measuring impedance
I am designing and building circuits which use 100Mb/s on a Low Voltage Differential Signaling (LVDS) bus. Some of these signals need to travel between PCBs on hand made cables. The problem is that I ...
1
vote
1answer
116 views
HCMOS drivers impedance table
I wonder, is there a table somewhere where I can find out impedance of drivers of various HCMOS series?
I am specifically interested in AC, ACT, LVC and HC series. I guess input impedance is very ...
1
vote
1answer
107 views
How to make a SCSI-3 terminator?
I have an old VAXstation that has an external SCSI Bus.
When I don't have anything attached to that, I get errors. I was thinking of adding a terminator, but those that I found online are quite ...
2
votes
2answers
245 views
DDR2-SDRAM Termination methods: passive vs. active
for a project I'm designing I am currently using a simple parallel Resistor Termination on the DDR2-Traces. But I'm wondering, what is the advantage of using a voltage regulator with ...
8
votes
5answers
7k views
How termination resistors work; what happens if I use lower values?
I am going to try to interface low-speed 8bit DDR2 chip to FPGA, and I've got some questions crucial to make it work :-)
Is that correct that the idea of termination resistor is to sink most of the ...
3
votes
1answer
256 views
Do DDR2 chips and controllers have on-die termination?
I am going to try to interface a low-speed 8-bit DDR2 chip with an FPGA, and I've got some questions crucial to make it work:
Is that correct that there is on-die termination on both DDR2 memory and ...
