LCDInfo.com

http://www.lcdinfo.com
It is currently Fri Mar 29, 2024 15:47

All times are UTC + 2 hours




Post new topic Reply to topic  [ 5 posts ] 
Author Message
 Post subject: USB 2 LVDS
PostPosted: Thu Dec 11, 2003 16:29 
Offline

Joined: Tue Dec 02, 2003 12:03
Posts: 107
Location: South Africa
Hi,

I have two old laptop lcds (LVDS Interface). I was wondering, will it be possible to build a usb interface for them? Then I can modify my media player to render the video stream to these lcds? What speed do you think I can achive? Else I just want to use them as picture frames? Via usb, update the picture on the screen every 15 minutes? What is the possibility of LCDInfo to support LVDS, etc.

_________________
Rudi Grobler


Top
 Profile  
 
 Post subject:
PostPosted: Thu Dec 11, 2003 16:38 
Offline

Joined: Tue Dec 02, 2003 12:03
Posts: 107
Location: South Africa
OK, so LVDS was not the correct word :oops:

Quote:
Short for Low Voltage Differential Signaling, a low noise, low power, low amplitude method for high-speed (gigabits per second) data transmission over copper wire.

LVDS differs from normal input/output (I/O ) in a few ways:


Normal digital I/O works with 5 volts as a high (binary 1) and 0 volts as a low (binary 0). When you use a differential, you add a third option (-5 volts), which provides an extra level with which to encode and results in a higher maximum data transfer rate.


A higher data transfer rate means fewer wires are required, as in UW (Ultra Wide) and UW-2/3 SCSI hard disks, which use only 68 wires. These devices require a high transfer rate over short distances. Using standard I/O transfer, SCSI hard drives would require a lot more than 68 wires.


Low voltage means that the standard 5 volts is replaced by either 3.3 volts or 1.5 volts.


LVDS uses a dual wire system, running 180 degrees of each other. This enables noise to travel at the same level, which in turn can get filtered more easily and effectively.


With standard I/0 signaling, data storage is contingent upon the actual voltage level. Voltage level can be affected by wire length (longer wires increase resistance, which lowers voltage). But with LVDS, data storage is distinguished only by positive and negative voltage values, not the voltage level. Therefore, data can travel over greater lengths of wire while maintaining a clear and consistent data stream.

_________________
Rudi Grobler


Top
 Profile  
 
 Post subject:
PostPosted: Thu Dec 11, 2003 16:44 
Offline

Joined: Tue Dec 02, 2003 12:03
Posts: 107
Location: South Africa
Quote:
LVDS
Low Voltage Differential Signaling (LVDS) is a new technology addressing the needs of today's high performance data transmission applications. It is also designed to meet the needs of future applications since the power supply may be as low as 2V. This technology is based on the ANSI/TIA/EIA-644 LVDS Interface Standard.

LVDS technology features a low voltage differential signal of 330mV (250mV MIN abd 450mV MAX) and fast transition times. This allows the products to address high data rates ranging from 100's Mbps to greater than 1 Gbps. Additionally, the low voltage swing minimizes power dissipation while providing the benefits of differential transmission.

The LVDS technology is used in simple line driver and receiver physical layer devices as well as more complex interface communication chipsets. The Channel Link chipsets multiplex and demultiplex slow TTL signal lines to provide a narrow, high speed, low power LVDS Interface. These chipsets provide dramatic systems savings in cable and connector costs, as well as a reduction in the amount of physical space required for the connector footprint.

LVDS solutions provide designers with a new alternative to solving high speed I/O interface problems. LVDS delivers Megabits @ milliwatts for today's and tomorrow's bandwidth hungry data transmission applications.

_________________
Rudi Grobler


Top
 Profile  
 
 Post subject:
PostPosted: Fri Dec 12, 2003 11:29 
Offline

Joined: Sun May 05, 2002 22:05
Posts: 2063
Location: Lappeenranta, Finland
Do you have some datasheets or some specs of the displays ? Usually displays like these require separate controllers that can cost quite a lot.

But if there was some controller chip it could probably be interfaced to a microcontroller and USB bus.

Larger displays are usually better to connect to VGA out though.


Top
 Profile  
 
 Post subject:
PostPosted: Fri Dec 12, 2003 11:59 
Offline

Joined: Tue Dec 02, 2003 12:03
Posts: 107
Location: South Africa
Yes, thy are a bit more complicated but not impossible. Thy usualy use 18 or 24 bits to control them. From what I can understand it is possible to connect them like this. I found a chip that drives the lvds and also a chip to control the usb. I am looking into a pic that i can use to controll and manage both. Will have a look for a datasheet!!!

_________________
Rudi Grobler


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 5 posts ] 

All times are UTC + 2 hours


Who is online

Users browsing this forum: No registered users and 30 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group