INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Jobs

decipher this german circuit

decipher this german circuit

(OP)
http://patentscope.wipo.int/search/en/WO2006015713

What does the circuit in the above link do? We've been asked by a client to look into using this to combine power sources with different voltages into a "halfway voltage" power supply. E.g. Input 5V and 3V supply and out the other side comes a 4V supply. I can't make heads or tails of the circuit in the link. Simulations aren't matching up to what the breadboard proto does either; I can provide more details if anybody is curious, but neither supports a the requested use case. Any ideas?

RE: decipher this german circuit

(OP)
Ah ok. Thanks. How would it buffer the voltage value of the resistor divider across to the output? I can't visualize how that would happen unless the FETs were operating in their linear regions, but that would be no good for a power source, no? To me, it looks like either the top rail being passed or the bottom rail being passed with a dead zone from -Vfet_threshold to + Vfet_threshold. Is that not the case?

RE: decipher this german circuit

No, they're source followers, so they'll follow, with a FET threshold drop, the voltage at the tap in the resistor divider. If this is what you want to do, the LH0063 would probably be a better choice, since it's got something like 98% gain, which is better than the circuit in the patent, and it'll supply a reasonably amount of current. http://www.datasheetarchive.com/dl/Scans-063/DSA2I... the original National Semi datasheet. ~1/4 amp from the LH0063.

Alternately, if you want to buffer the voltage divider, a simple power op amp circuit would be less of a bother, since its gain would be in the 99.9% range.

TTFN
FAQ731-376: Eng-Tips.com Forum Policies

Need help writing a question or understanding a reply? forum1529: Translation Assistance for Engineers

RE: decipher this german circuit

(OP)
Got it now. Thanks!

RE: decipher this german circuit

A patent on a complementary source-follower charging a couple of caps?

Wow... just wow...

Apart from that, if the FETs are depletion-mode types, the circuit will work. But those are scarce nowadays.

Benta.

RE: decipher this german circuit

As a native German speaker I'd like to shed some light into the topic:

on the circuit itslef:

This is not a circuit for signal processing but for power. In power elctronics e.g in Inverters connected to 400 V three-phase mains, electrolytic caps have to be connectec in series due to their Limitation in voltage rating. To balance the voltage parallel resistors have to be added, creating significant no-load losses. The circuit ensures proper voltage sharing with much lower losses.

On patent law in the ROW (Rest of world, not US): The document attached is an international patent application, not a granted patent. According to depatisnet - an internet service of the german patent office - no national patent related to this application was granted anywhere.



Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close