18 Threads found on edaboard.com: Power Supply 723
If you want to "play" with electronics then a regulated power supply is a "must".
If you can adjust voltage (3-30V is a handy range) and adjust the current (0-2A is also a handy range) then in many cases you will be safe trying new circuits or testing components.
The simplest adjustable regulator is based on very popular voltage regulator, the LM
Electronic Elementary Questions :: 10.07.2005 03:05 :: IanP :: Replies: 18 :: Views: 15959
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: 15481
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: 842
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: 1972
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: 1156
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: 1314
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: 840
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: 1489
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: 2994
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: 2112
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: 2319
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: 4404
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: 2726
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: 498
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: 666
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: 867
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: 464
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: 401