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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Low-Voltage Differential Signalling (LVDS) not working
I have updated the schematic and hopefully included all the suggestions.
The problem of the LED strip flickering is still there, however, I have noticed a slight improvement after altering the circuit ...
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LVDS oscillator's complementary output does not swing
I am using a SIT9121 27 MHz LVDS oscillator. The MPN is SIT9121AI-2B2-33E27.000000
The circuit design is shown below.
The 100 Ω resistor is right at the oscillator's output (about 2 mm distance track)....
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How to get a clean clock signal from FPGA to DACs?
I have the VC707 FPGA board and an external reference clock (fairly clean 100MHz), that I want to use as a reference for a 200MHz generated clock on my board. Then using this clock to clock my DACs (...
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What is the difference between PN- and PM- Differential pairs?
I am looking in the past recent weeks in a lot of datasheets and I see PM labels for LVDS (Low voltage differential signals) or generally Differential pairs on the Block Diagram. Altium would ask me ...
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What are the most effective techniques for reducing the negative effects on differential pairs routed on top of two different ground planes?
I have an FMC Card with analog circuitry containing channels. I've separated the ground for these analog channels into two distinct planes: AGND and PGND.
PGND serves as the ground for the power ...
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Connecting LVDS to oscilloscope using ferrite bead to isolate GND/SHIELD
I want to measure LVDS signals with a scope.
Will my solution work? (Shown at bottom.)
I know of other ways of doing this, but I am hoping this way is cleaner and easier.
Specs:
Frequency:~100MHz
...
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Can Raspberry Pi be used for LVDS image signal reconstruction
I have a NOIP3SN5000A image sensor manufactured by Onsemi with a LVDS output. I would like to reconstruct the output signals into images by a Raspberry Pi 4B, can it work?
I have seen a lot of ...
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Expected Outcome of a LVDS Transmitter Output if there's no Termination Resistor
I know this sounds like a silly question, but what would the expected waveform of a LVDS transmitter that has no termination resistor look like? If the expected output were to be a 20 MHz LVDS clock ...
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The best way to light an LED at a distance
I need to control an LED (SSR) at a someway-long distance of about 20 meters (60 feet) from a microcontroller.
A simple LED on/off control type where I could keep it on for a long period of time. The ...
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20-pin LVDS (DF14-20P) to USB/HDMI for post-processing?
I am looking to convert a 20-pin LVDS (DF14-20P) signal from a thermal imager to another format (i.e. HDMI) so that I can do post-processing on a Raspberry Pi, OAK-Som, or similar.
Everything I can ...
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LVDS to Singled-Ended - Transmission Line Balun Matching
I need to convert a LVDS clock into a single-ended signal. In the past I've used a voltage balun with a center tap on the secondary but I haven't found any good past 1GHz. I need to get to 2GHz in ...
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Can AC Coupled LVDS be used in a multidrop architecture
I am designing a system with a clock distribution IC with AC-LVDS outputs.
I would like to connect this into a multi-drop LVDS system. All LVDS receivers will be operating off the same voltage levels.
...
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No light detected from 1310 nm IR optical transceiver AFBR-5813TQZ
I am trying to build a test application circuit for an AFBR-5813TQZ IR (1300 nm) optical transceiver. For now, I am only trying to verify that the transmitter works, so I have breadboarded the ...
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translating LVDS to LVTTL using amplifier and high speed output buffer
I am receiving an LVDS clock differential signals and need to convert them to LVTTL .
the problem is that the LVDS frequency is above 500Mhz and the LVTTL output needs to drive a 50ohm resistors, when ...
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LVPECL output circuit explanation
I don't understand the circuit itself, how we will get VOH and VOL on the outputs. There is 2 modes one mode is when Q1 is conducting and the other mode is when Q2 is conducting , how from here how ...
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How can I translate LVDS to LVTTL with limitations?
I want to convert LVDS differential signals to LVTTL.
I have 2 limitations:
The frequency of the LVDS signal is around 500 MHz.
The LVTTL voltage output should be around 2.4 V and it needs to drive a ...
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How to get 70" LCD with LVDS connector to work? Is matching 2ch 8bit interface needed?
I have two working 1080p 70" Panels but the interface board is quite custom and somehow broken - the HDMI input just causes some flickering at most.
I already did a lot of research but I did not ...
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LVDS pin configuration
I'm trying to drive a LVDS display. However, there are pins that I don't know about their functions and how to apply signal to it:
DIMO (Output): Backlight CABC controller signal output
CABC_EN0 &...
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What is the name of the controller that turns a framebuffer to an LVDS signal?
I've been googling around for a bit and I'm having trouble coming up with the term for a device that takes in an address and a color and saves it to a frame buffer then sends that frame buffer over ...
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Creating a 10MHz clock grid
I have a round surface of 1.5 meters in diameter that contains many electronics. What I would like to do is distribute a 10MHz 3.3V clock signal from Teensy 4.0 across the table for 200 ADCs to access ...
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Will the LVDS signal rise time improve after a counter IC?
I want to improve an LVDS signal's rise and fall time. With a Cyclone III FPGA, the LVDS signal has a 500 ps rise and fall time.
If I apply these signals to a counter/divider IC like the SY100EP33VKG ...
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LVDS vs driver strength in FPGA IO
In the FPGA, there is I/O constraints that can be done to configure the output buffer. Some of these constraints are like setting the output drive strength parameter, on die termination, output delay, ...
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Help identifying LVDS display connection type
I have a new motherboard arriving with this connector attached but I need help identifying what display type this LVDS connector uses. I don't think it's MIPI or the standard LVDS but I can't tell.
In ...
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Should LVDS SerDes communication be with or without driver?
I have LVDS SerDes signals coming out from FPGA1 IO and have a few questions regarding the design.
My plan is to output the signals from the FPGA1 to a connector and from the connector a cable will be ...
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How to calculate the maximum cable length for SerDes using data isolator component?
I am using ADN4655 component to isolate LVDS SerDes lines that run at 1GHz.
https://www.analog.com/media/en/technical-documentation/data-sheets/ADN4654-4655-4656.pdf
Termination 100Ohms resistors are ...
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Reference plane in small PCB
I have a small PCB, 6mm by 16mm with 6 layers. There are LVDS SPI signals (4 pairs) on this PCB, but due to the density and size of this board, it was difficult to have a reference plane under the SPI ...
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What are the recommended CK, DQ, DQS, ADDR impedances for LPDDR4?
I am using a micron part with LPDDR4, in many datasheets from micron there are no references to a specific impedance for CLK, DQ, DQS, ADDR. The datasheet mentions that the LVSTL is tuneable, but what ...
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LVDS voltage levels
LVDS terminology can be a bit confusing when noted that Vcm typically is 1.2V and Vd 350mV. Does this mean 350mV as in +/-350mV so (Vin+ - Vin-) is (2*350mV) or overall swing (peak to peak of a ...
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Formula for coupled stripline of 100 ohm
I am designing a PCB which involves MIPI and LVDS routing.
What is the formula to calculate the impedance of asymmetric coupled stripline for MIPI and LVDS routing (100 ohm)? The required calculator ...
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What is the standard common mode voltage of Media Dependent Interface MDI[0:3]± signals?
I am working on the selection RJ45 connector for MDI interface between PHY and the link-partner.
I am planning to use this PHY for my SGMII interface application. From various online readings, I ...
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What is the SGMII differential peak to peak voltage?
I am trying to understand the SGMII Driver and Receiver DC specification. Here is the link to SGMII specification - SGMII.pdf I am studying.
Table-1: Driver DC specification
Table-2: Receiver DC ...
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Is it possible to convert LVDS (TI DS90c241/124) differential signals to optical signals?
I have a circuit that uses the TI DS90C241 DS90C124 serdes pair to serialize 24bits of data from one board to the other. Either due to electrical interference or the transmission media's ...
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Interface a CML device with FPGA
I want to interface an IC with an FPGA however I noticed that the datasheet says the digital control inputs are differential and CML standard based. Can someone please guide how to interface this if I ...
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How can I drive an LP101WX2 LCD panel with the Chalkboard Electronics HDMI-dualLDVDS converter?
I am trying to drive an LP101WX2 panel with the Chalkboard Electronics HDMI-dualLDVDS converter but all I am getting is a black screen.
I tried to flash the board's firmware with both the demo and the ...
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When can you AC couple LVDS?
According to Wikipedia Wikipedia-LVDS, 350mV signal (700mV differential) is developed when a 3.5mA current flows through 100 ohm differential resistor. and according to this app note from Analog ...
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What values should be checked for SGMII signal compatibility?
How can I verify the DC electrical compatibility of the SGMII signal between PHY and MAC (within FPGA)?
Here is the reference-design that I am working on. Page 40 is using a Marvel PHY that is ...
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How to connect Mini LVDS to standard LVDS or HDMI?
I've purchased a LCD TFT Display (LG Display LA123WF-SL01) that has an absurd connecter that i haven't seen anywhere online that it has been used before. The name of the connector is FH28D-64S-0.5SH.
...
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LVDS rise/fall time measurements - confused
In a document I found they mention that the rise/fall times are measured over 20-80% of the signal. They mention that the common mode is 1.2V with a output voltage swing of 350mV.
This all makes sense,...
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Consequences of having an external signal connected to an output of a LVDS Receiver?
I am trying to debug an issue with an LVDS receiver on a fellow colleagues board. They are using an LVDS differential pair from an FPGA to control a reset line on a MPU on their board. For debugging ...
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LVDS: Higher skew deviation or termination resistors as close as possible to the IC
I am designing a pcb with a video interface which runs lvds. LVDS has termination resistors and the datasheet states to have them put as close to the IC pins as possible. It's not 4k, but close to ...
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Purpose of split termination in differential pairs
Can anyone tell me what the purpose of split termination is in a differential pair?
If you look at the LVDS article on Wikipedia, you'll see the 100 Ohm termination resistor in parallel across the two ...
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How can I bridge across a change in differential impedance?
In a design I'm working on, I have a 100Mbps differential signal traveling from a chip on one PCB to a chip on another PCB. For various reasons, I can't make the differential impedance the same on ...
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One Differential end into Single Ended Input
I am trying to test a LvPECL signal into a LVDS receiver (NI 6583). Unfortunately, I currently only have the single-ended segment/connector. Looking at the spec, the single ended receiver should still ...
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Comparator merge analog and digital grounds [closed]
My schematic looks like this:
simulate this circuit – Schematic created using CircuitLab
How should i connect ground and power supply to comparator? I have some signal which i want to convert ...
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Can you integrate an LVDS with a common RS485 if the RS485 is used as a discrete and not a digital serial signal? [closed]
Is the LVDS compatible with an RS485 signal? Can i integrate 2 systems in this way?
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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, ...
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Sniffing a SPI BUS
I want to sniff some data from a SPI Bus between boards from a loom machine. The bus starts at J9 from PCB 5722 and goes through 8 boards named PCB 5778, which I guess are the slaves. The connector ...
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Difference between LVDS, MIPI, DPI and DSI
I'm on a project that involves TFT displays and Raspberry Pi Compute Module 4. I noticed that there are several acronyms, protocols confusing information.
As I understand it, there are protocols:
DBI:...
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How can I identify this QFN IC marked GX?
I'm trying to identify what this part could be based on the top marking, GX, but I've been totally unable to find it online. I'm pretty sure the packaging is QFN, it has 16 pins, and I know it has ...
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How do terminate the coax shield of AC coupled LVDS signal? (isolated grounds)
I have an LVDS clock signal that goes to several PCB cards. Frequency: 100Hz --> 20MHz
I am going to use a fan out IC to supply each card with it's own buffered CLK signal; I am not going do a '...
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