Questions tagged [lvds]
LVDS stands for Low Voltage Differential Signalling. It is a popular high-speed (>100 Mb/s) way to connect chips.
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Detecting activity on LVDS line
For some test equipment I have an LVDS line running at 100 Mbps. I would like to make an Arduino Due (because I use this for other monitoring in the test) detect activity on the LVDS line.
Using a (...
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0answers
22 views
LVDS25 LVDS33 and LVDS18
I am a little confused about the definition of LVDS_18, LVDS_25 and LVDS_33.
I thought LVDS simply had a VCM of 1.2V. If a clock calls for LVDS25, can I run an LVDS clock from a part that is being ...
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1answer
44 views
9-pin micro-d connector for LVDS signals
Has anyone utilized 9-pin micro-d connectors for driving and receiving LVDS signals? I am running the LVDS at 100 Mbps for 20-30 inches.
I am using a vertical pcb mounted connector 380-009-213 from ...
0
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1answer
61 views
Using DB9 connectors for LVDS signals
Has anyone utilized 9-pin DB9 connectors for driving and receiving LVDS signals? I wanted to use Micro-D connectors on a board I am developing but they take too long to get. Since DB9 connectors are ...
0
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1answer
90 views
How do I configure the wires in the LVDS 30 pin cable?
I explain:
I have a screen that I want to use as a monitor. I have purchased an LCD controller board and a LVDS cable
I need someone to help me to rewire the LVDS cable. I have the input terminal pin ...
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0answers
58 views
LVDS (from PTN3460) driven display shows fringed lines
I am developing a board which converts DisplayPort to LVDS. The LVDS is put through a PCIe switch and then fed to an APIX transmitter, which connects to the display.
There's a second video path going ...
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0answers
50 views
Connecting CMOS sensor to (far away) PCB: understanding cable length
The problem is a bit complex due to the number of unknown parameters and my inexperience. I need a way to determine how far I can put the PCB from the sensor without problems in the transmission of ...
0
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1answer
63 views
ADC with parallel DDR LVDS interface and also a parallel CMOS interface
The ADS4126 is a 12-Bit, 160-MSPS Analog-to-Digital Converter (ADC). Its data rate is too high for it to be read out using something like SPI or I2C. It does use SPI for control purpose though.
The ...
2
votes
1answer
69 views
Signal 'bounces' back to high
I transmit a signal using LVDS over a CAT6 ethernet cable. However, instead of coming through clean, it always 'bounces' back to the high state: (Pink is the input and yellow is the output)
(Sorry ...
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1answer
57 views
Impedance Mismatch of LVDS Differential Pairs
A mistake was made when designing a set of mother and daughter PCBs, resulting the daughter board to have its LVDS pairs at ~100Ω differential impedance, while the motherboard ~90Ω. The receiver, ...
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1answer
55 views
How to generate positive and negative power supplies from a single supply with high current driving capability?
I am trying to build a 1553 military standard bus transceiver (analog front end) and I am required to use a single power supply of 3.3 V. To be able to receive, my comparators need supplies of +/- 3.3-...
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0answers
45 views
LVDS length pair matching (HSD connectors)
For a high speed interconnect (3 - 6GBit/sec over a single lvds pair) I attempted to length match the LVDS data pair as accurate as possible. Something I have failed to get information on is the ...
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1answer
58 views
Understanding Common mode voltage
I am trying to understand common mode voltage a little bit fundamentally (only with electronic devices and no math).
I watched this Youtube Video to understand common mode and differential mode ...
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0answers
52 views
Universal LVDS controller board
I am trying to salvage a Chimei Innolux V236BJ1 LE1 panel from an old LG TV. Planning to use T.RD8503.03 but I can't find the datasheet. I need it to see if the pinout are compatible, or if not, to ...
0
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1answer
78 views
LVDS data rate to TFT
I have a two LVDS Ports (A & B) coming from deserializers connected to a 10.25" TFT display.
lvdsaclkp, lvdsaclkn, lvdsa[0:3]p/n
lvdsbclkp, lvdsbclkn, lvdsb[0:3]p/n
VESA:
JEITA:
What is the ...
0
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1answer
30 views
Circuit not working: Differential impedance, or skew, or a different problem responsible?
For a hobby project, I am designing a circuit that converts displayport to APIX2, which is a serializer protocol used in cars' infotainment systems, mostly BMW. This is done by an INAP375T IC, APIX is ...
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0answers
61 views
Interfacing LVDS into LVPECL with DC coupling
We are using TI ADC ADC12DJ3200 in our design.
Now this ADC has input pins for timestamping the ADC data.
This timestamp input supports LVPECL standard but the allowed common mode voltage is only 0....
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1answer
67 views
Why a potential divider at high speed LVDS clock outputs?
I recently came across a Xilinx SOC design in which the system clock which is configurable up to sub GHz, being an LVDS clock the output is been divided using a 1.2V rail, as shown below.
Will this ...
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2answers
138 views
From where does the Common Mode 1.2V of LVDS comes from?
I am trying to understand the LVDS signalling.
But from where do we get the 1.2V common mode voltage?
Please help.
Thanks
0
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2answers
91 views
Can I use a deserializer without a matching serializer?
I am trying to connect an LVDS output to an 18-bit parallel input. Ser/des ICs like this all state on their datasheets (like on page 12 of the linked datasheet) that before they are able to function ...
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0answers
54 views
Signal conversion LVDS, RS422 and LVTTL
What are all the parameters required to LVDS to lvttl, RS422 to LVTTL and LVTTL to LVDS and RS422 signal conversion?
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0answers
30 views
DS90UB948-Q1 internal pattern generator
Does anyone have prior experience with DS90UB948-Q1 FPD-Link III Deserializer deserialiser from Texas Instruments ? I am trying to configure the internal pattern generator block sending I2C commands. ...
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0answers
930 views
Connecting 21" screen to LVDS connector on motherboard
I'm working in an "All-in-One pc" project. For that, I have an old Dell laptop (which only works with DC adapter) and a 21" LG monitor.
My question is: How can I connect the LCD panel directly on the ...
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0answers
155 views
Test LVDS signals
I am wondering how I could test LVDS signals on a PCB using a scope.
The most straight forward answer would be to measure on the termination resistor points, although this isn't possible, since the ...
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0answers
62 views
sub-LVDS to CSI-2
I am going to make two prototype boards with the same functionality but using different components.
For the first prototype board, my question is related to this topic. The imaging sensors I'll use ...
2
votes
2answers
88 views
Can CML differential signal lines be flipped to act as a NOT gate?
If I want to invert a CML differential D-Flip Flop (Ex: hmc747lc3c) output before entering into a CML Counter(Ex: MC10EP016), is it as simple as flipping the signal lines before entering the counter? ...
3
votes
1answer
500 views
Maximum length of high-speed LVDS cable in automotive environment versus using SerDes
I would like to connect a small TFT display that uses LVDS, 4 channels for data and 1 channel for clock. Data rate is maximum 200 Mbps per lane. Very strict EMC requirements are applicable, namely ...
3
votes
1answer
163 views
Debugging dual LVDS display panel color issue
I'm on TI's AM5708 platform (custom board) trying to drive this Full HD panel via TI's DS90C387 Dual-Pixel Display Interface.
The SoC outputs 24bit RGB into ...
1
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1answer
366 views
Differential Pair Reference Plane Coupling
I am routing LVDS pair on a flex board. The signal is 264MHz. I used Saturn PCB design to calculate width and spacing between conductors. The targeted impedance for diff pair is 100 ohms, which is ...
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0answers
194 views
LVDS driver signals measurement
This is background: I have a self-made PCB, which is used to connect the camera via the CameraLink interface.
When I connected everything together, it turns out that the camera is signalling me via ...
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1answer
324 views
LVDS display troubleshooting
I am currently working on a prototype connecting a SOC-board (Samsung ARTIK530) to a LVDS LCD display (DT070BTFT-PTS1).
The display shows a very (!) distorted picture.
I have tried fixing it using ...
0
votes
1answer
603 views
Word alignment / bitslip in LVDS Receiver
I am simulating the Soft LVDS IP core as receiver by passing a bit stream with IP core parameters configured as follows:
Power Supply Mode: Dual (for 10M50DAF484C7G)
Functional mode: RX
Number of ...
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1answer
530 views
Does LVDS always need 100 ohm differential impedance?
LVDS pairs need 100 ohms differential impedance. However, I am having trouble achieving that in my design.
My design requires that the pairs travel over very thin flexible PCB, about 50mm total ...
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votes
1answer
215 views
Locating pairs on an LVDS cable
For a 2-row connector intended to interface a cable to a PCB, which method is preferable for twisted pair LVDS signals?
Horizontal Pairs:
LVDS1- LVDS1+ ...
0
votes
1answer
128 views
Why does LVDS (or any differential signaling for that matter) use a common mode voltage of 1.2V instead of 0V?
Why does LVDS (or any differential signaling for that matter) use a common mode voltage of 1.2V instead of 0V?
Is there an easy way to shift the common mode voltage to 0V?
3
votes
1answer
354 views
How to “Pull Down” LVDS input in FPGA
One of my hardware modules uses a state machine which is triggered when the input signal IN is HI (that's an LVDS pair on Microsemi proASIC FPGA). The problem arises when nothing is connected to the ...
0
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1answer
174 views
How to use 0.1 inch header footprint for high speed signals?
I have a board which has a dual 0.1 inch header footprint (the totally standard kind you see everywhere). Trouble is, this carries a fast 300-500 Mbit DDR LVDS signal (!!) to another board. Okay, so ...
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1answer
502 views
What lvds connector do I have
Can someone help me find out what type of LVDS cable I have and point me in the direction of an adaptor to HDMI.
Thanks.
Backstory:
I recently had to throw out an old Sony Vaio All in one PC and ...
3
votes
1answer
938 views
SPI with differential signaling
Standard SPI uses single-ended signals. Is it possible that a communication uses SPI protocol but the signals are physically LVDS?
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1answer
422 views
Non-coaxial 50 ohm cable for LVDS
I'm looking to configure a Xilinx Zynq-7000 custom board with LVDS receivers according to the following diagram.
In my setup, the 'IOB' on the left represents an LVDS driver from a radar receiver and ...
0
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2answers
211 views
LVDS Flex Cables - Optimizing Trace Layout for 10 GbE
I want to run a 10 Gigabit Ethernet (GbE) signal over a 15 pin LVDS flex cable like this one:
My PCB will accept an RJ45 connector, and those traces will run over the PCB to the flex jumper, then ...
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1answer
383 views
Setting DC-bias on LVDS receiver with internal 100ohm differential termination
Here is the setup :
simulate this circuit – Schematic created using CircuitLab
RX channel is routed as 100ohm controlled impedance. FPGA input pins are LVDS IOs. I want to apply a DC bias of +...
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0answers
344 views
Alternatives to RJ45 ethernet connections?
I have a system where two boards need to communicate through a serial bus with several lines --- rates are in the order of up to 3MHz. The boards will be several meters away (say, 3 to 5 meters / 10 ...
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0answers
106 views
LVDS CLK Input Appropriate Here?
I'm working with an MCP37231/21-200 that requires a differential input for the clock. I need to know if I can use an LVDS input to drive my clock. The output clock is specified to have LVDS ...
0
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1answer
418 views
does the orientation of a choke in an LVDS application matter?
I found the diagram below online while looking for information on the orientation of a choke I intend to use in an LVDS application. Does the orientation of the choke matter? The part I intend to use ...
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0answers
994 views
Interfacing LVDS to 1.2V IO Bank (e.g. POD12 or SSTL12)
I am currently working with an Arria 10 device (specifically a ReflexCES A10 SoM Indus module). The GPIO pins of the device are split into IO banks with specific VCCIO voltages controlling the banks.
...
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2answers
947 views
Using old laptop LCD as external VGA screen [closed]
I have a few old laptops with good LCD panels that I wish to salvage and use as external VGA screen on other computers.
I'am no expert in electronics but I work with computers and know the basics of ...
0
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1answer
113 views
FMC connector AC701
I am using the AC701
I need to use the pins of the FMC connector to connect the outputs of 8 ADC to the inputs of the FPGA ( 41 pairs of LVDS signals)
I need to use the pins of the FMC connector to ...
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votes
1answer
120 views
LVDS inputs and TTL outputs in design
I have a design and most of the entry ports are the outputs of an ADC these outputs are LVDS.
My question is how do i declare the inputs of my FPGA as LVDS signals?
And how to declare the outputs has ...
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vote
1answer
116 views
Which is better, less crosstalk or less skew?
I'm designing a board that has a LVDS 2.5V interface with 30 lanes clocked at 600MHz and DDR. This is going from one chip to another chip which could be placed right next to it, there are no other ...
