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.

How To Draw 5V 100mA from 3-phase without transformer?

Status
Not open for further replies.

Sobakava

Full Member level 6
Full Member level 6
Joined
Mar 27, 2002
Messages
350
Helped
8
Reputation
16
Reaction score
8
Trophy points
1,298
Activity points
3,342
I want to get 5V 100mA DC from 3-phase 380V mains without using transformers. I tried capacitor-resistance in series and 3phase bridge but can't draw so much current.

I'm trying to get power for my board without using transformers to keep it low cost, I do not need galvanic isolation for this board.

Could you advise me a schematic to try?

Regards
 

Is it STAR or DELTA configuration .. or in another words, is the NEUTRAL available?
Regards,
IanP
 

yes I've neutral also.
 

In ths case I would select only 1 phase and neutral, and use the attached circuit with the following changes:
FS - 250mA
FR = 0
R1 = 10Ω
C1 = 3µF
ZD1, ZD2 = 8.2V
C2 = 470µF
ZD3 = 5.1V/5W
Regards,
IanP
 

I need to use all 3 phases because, I want that circuit will continue to work even if 1 or 2 phases from main supply becomes cutted.
 

Take a look at the attached circuit ..
It takes power from all 3 phases ..
The 5.1 zener diode should be at least 5W ..
Regards,
IanP
 

how much current can I expect from this circuit?
 

I would say >150mA ..
Regards,
IanP
 

    Sobakava

    Points: 2
    Helpful Answer Positive Rating
I suppose that circuit for 3 phase 5 V wont work . Once capasitors charged then wont transfer charge in forward direction through diode .
And also that circuit on picture is not optimized

2 Sobakava . Take a look to converter alike solution (let say chargers for ericsson mobiles ) . They are littel bit more complicated than what you are trying to do .
 

    Sobakava

    Points: 2
    Helpful Answer Positive Rating
Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top