Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Solution for implementation of SCART switch

Status
Not open for further replies.

Zhasha

Junior Member level 3
Joined
Dec 3, 2005
Messages
30
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,286
Location
Denmark
Activity points
1,643
Hi

I recently thought of a project that seems simple, but still i cant figure out
what i want to do is have a chip control 2 SCART inputs and 1 output.
i want it to be able to select which of the 2 gets forwarded to the output (so its just a matter of forwarding signals)
but i dont want to use 42 transistors for the job, so i would like to know, what are my options?

Thank you in advance
 

Buriedcode

Full Member level 6
Joined
May 6, 2004
Messages
357
Helped
43
Reputation
86
Reaction score
7
Trophy points
1,298
Location
London
Activity points
8,887
scart switch ic

Hi,

I've never done this before, and my knowledge of the 'SCART' standard, and video, is limited..

Most scart switches are mechanical, with lots and lots of poles. As for making an 'electronic' switch, I wouldn't want to use '42 transistors' either ;) But you won't have to. Even though there are 21 pins, theres only really video, and 2 audio lines.
Each having their own 'GND'. I've yet to find a 'retail' scart switch that uses separate GND lines....so, just connect them all up. so, really, you need a 2-way, 3-pole switch. Of course, you can add the 'auto' pin to the switching...the one that automatically switches a device to the scart channel when the pin is high.

I suppose you could use 'analogue' switches - but they have their limitations. Because the video/audio level in SCART leads is pretty small (1v p-p?) they should work....but you may get cross-talk between the switches in the same package.

Heres a few links, that relate to video switching/analogue switches to get you started..

http://www.cs.ubc.ca/~jennings/vid_sw/html/article.html
http://www.amabilidade2002.com/scartrs3.htm
http://www.st.com/stonline/products/literature/ds/9754.pdf - if you want to go hardcore...and build a huge switching matrix with 'big' chips :D

http://www.maxim-ic.com/SwitchMux.cfm - probably your best bet. And they send samples......provide schems etc...

If you want an easy life, you could just use a mechanical switch with a solenoid. Not pretty, but it wouldn't effect the signal quality.

My two pennies.

BuriedCode.
 

Status
Not open for further replies.
Toggle Sidebar

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top