18 Threads found on edaboard.com: Power Supply 723
I'm looking to build a variable power supply for my second electronics project (the first being the transistor tester I inquired about here a few weeks ago). I'd like a few recommendations on what I should build.
So far I'm thinking that a 3-30 volt design (of which there seem to be many) would work whether I am doing something that involves sm
Electronic Elementary Questions :: 10.07.2005 02:06 :: shellcode :: Replies: 18 :: Views: 15917
Hi there, please help me, i tried to make a power supply using LM723 which its voltage "should" be adjustable from 0-30V/2A. I get the circuit schematic from internet, but after i make it on the breadboard, the results which i get is differ from what is says on the tutorial. I get 3V instead of 0V as the minimum voltage. please help me with (...)
Electronic Elementary Questions :: 14.10.2006 02:19 :: zhi_yi :: Replies: 2 :: Views: 15354
I am wanting to power a 12v computer fan for long periods of time seperate from the computer.
I have snipped the end off of a walkie talkie charger and ive been told not to use chargers but this cord was plugged into the base where you put the walkie talkies at, and i think the cable its self could be safe enough to power the fan.
On the plug-in
Electronic Elementary Questions :: 13.10.2007 10:41 :: Johnnyy :: Replies: 7 :: Views: 835
Hello every body.
First of all i am a new member so it is good to say hello every one on the forum.
Now the actual problem. I need the circuit schematics of variable power supply, it is a kit i bought it some time ago. The kit markings are Cana kit R051. I made some crazy mistake while using it and managed to burn few components resistors.
Hobby Circuits and Small Projects Problems :: 01.02.2010 10:13 :: Zibtek :: Replies: 2 :: Views: 1943
Hi, I face current limiting problem in 723 based power supply (3-30V, 0-2A). I got this:
device and try to replace R5 (normaly 0.15Ohm, 5W) with standard 1k potentiometer. Unfortunatelly my pot is burning - I counted that it should
Power Electronics :: 15.11.2010 03:33 :: chrisdot :: Replies: 1 :: Views: 1088
This is a project of linear power supply for powering HF radios.
Components used in construction:
880VA transformer with two windings 15V each, wire 2,2mm
rectifying bridge ? 4 diodes from computer
Show DIY :: 26.10.2011 14:22 :: Vermes :: Replies: 0 :: Views: 1292
I need a precision voltage reference in wide range power supply
( 6v ~ 40v). Who has good idea to design the ic curcuit?
Analog Circuit Design :: 13.03.2005 23:56 :: mark_nctu :: Replies: 1 :: Views: 828
hello, i want to make a 0 to 12V variable dc power supply using lm 723.since Vref has to be more than 2V my o/p is in the range 2.something to over 14V. The problem i am having is in finding a virtual ground of around 2V.I put a 741op amp and used it as a unity follower with Vref of around 2V as i/p and +Vcc connected to unreguated (...)
Electronic Elementary Questions :: 12.06.2009 16:34 :: arin23 :: Replies: 3 :: Views: 1447
ur circuit seems like dual output voltage regulator...but there is no feedback form
the final point to regulation circuit .... and there is no short circuit protection...
u drive the base of 3 parallel 2N3055 with 1N4148 its just small signal diode..
i dont no why use 3 diode in serial may be to cancel 1.25V for lm317
Power Electronics :: 14.12.2009 10:09 :: nashwan :: Replies: 7 :: Views: 2930
I am planning to design a circuit to get a regulated +/- 15 V, +/- 100 mA using a "single
Which is the preferable IC, 723,78XX,79XX, or 317 ?
Can anyone provide the circuit configuration ?
Analog Circuit Design :: 19.05.2010 10:45 :: vinodquilon :: Replies: 2 :: Views: 2080
You have to use 723 in so called "floating configuration".
Basically, you need 2 independent DC sources.
One is rated with your output voltage, say 30V/2A. This voltage is connected to the series pass transistors (internal series transitor + external power transistors in darlington configuration).
The other dc source is say
Professional Hardware and Electronics Design :: 04.03.2002 20:19 :: matteo128 :: Replies: 2 :: Views: 2302
Here is application of 723 voltage regulator and 2N3055 power transistor:
Instead of potentiometer and R2 you can feed 0-5V through a voltage divider directly to (+) input of 723 error amplifier.
However, I don't believe that in this circuit you will be able to gener
Analog Circuit Design :: 23.09.2005 22:05 :: IanP :: Replies: 6 :: Views: 4373
Here is a concept of adjustable linear power supply based on descrite components and 723 voltage regulator:
For 30V output you will need to ensure that the unregulated voltage is >35Vdc and, of course, change th values of resistors around the potentiometer ..
Pre-regulation can be added to the above
Analog Circuit Design :: 11.06.2006 21:24 :: IanP :: Replies: 4 :: Views: 2705
I have created a small power supply based on a 723. The end transistor is a 2N3055 (max 15A acc. to data sheet) and the bridge rectifier is a VH447 (max 6A acc. to data sheet). These 2 components will get hotter as the power goes up.
The circuit seems to work OK but when I wanted to test the max. current (...)
Analog Circuit Design :: 10.05.2008 01:20 :: vckoopman :: Replies: 1 :: Views: 491
You did not mentioned the power rating or supply voltage. Use a regulated power supply (first test it on bench PSU and see the result).
RF, Microwave, Antennas and Optics :: 01.12.2008 03:42 :: Awarapunshee :: Replies: 8 :: Views: 657
I am recently design linear dual output power supply(+/-12V output and share com with other positive outputs),but I do now know how to start from scratch.Although the datasheet has detailed fig with each applicaiton.But I suppose it would not be so easy just assembled two circuits (positive and negtive ouput) together use a centre-tapped transform
Power Electronics :: 07.11.2011 21:20 :: jigshaw :: Replies: 0 :: Views: 822
I am making a variable power supply, but i have encountered a problem that i m getting 48 V DC after rectification of 36V AC. As i need 10 amp current and i read from some where that 1000uf/amp capacitor is recommended so i have total capacitance of 7000uf, is this the capacitance that is causing this abnormal behaviour? I havnt any circuitry to di
Power Electronics :: 03.05.2013 08:42 :: muneeb.khan :: Replies: 6 :: Views: 430
Are these calculations right ?
Rated apparent power A = 1565*660 = 1.033 kVA
rated power factor p.f. nom. = P/A = 900/1.033 = 0.87
φ = arccos 0,87 = 0,513 rad
tanφ = 0.563
rated reactive power Q = P tanφ = 900*0,563 = 507 kVAR
Let's assume minimum p.f. being 0.7!!!!....then tan φ1 = 1
Without any (...)
Electronic Elementary Questions :: 13.06.2012 13:38 :: dineshdeshmuk :: Replies: 4 :: Views: 390