Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics 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.

5.8GHz wireless AV link transmitter problem

Status
Not open for further replies.

jankro

Junior Member level 2
Joined
Jun 9, 2010
Messages
22
Helped
2
Reputation
4
Reaction score
2
Trophy points
1,283
Location
Finland
Activity points
1,403
I have a set of these and the transmitter has a heat sensetive four legged SMD chip inside the metal can. Picture disappears when this warms up and after cooling it, the picture re-appears.
I have not found any info about the chip. If anyone can help, I would appreciate it! :)
**broken link removed**

-Jan
 

Looking at the way it is used, I would suggest its a Hittite H251 prescaler. It seems to feed the Zarlink PLL (above it) from the oscillator (below it) and the SOT23 device looks to be wired as a charge pump in the PLL feedback path.

Brian.
 
  • Like
Reactions: jankro

    jankro

    Points: 2
    Helpful Answer Positive Rating
Great, thank you very much!!

Now, my next problem is where to get one of those beasts. A quick check showed that only some wholesale places have them and I don't think that I need thousand's of them ;-)

-Jan
 

They are probably obsolete, Hittite don't list them on their web site but they probably make a replacement type you could drop in instead. Try contacting them, they have a representative in Finand. The contact information is on their web site Hittite Microwave I find most companies are helpful and often let you have a free sample!

Brian.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top