please suggest me on opamp..

[rao]

Thank you sir

[rao]

Recently I came through ic 723 where it can do voltage control and current control. Please suggest some circuit where it could be variable

Voltage: minimum to 36V
Current:minimum to 1 amps.

I want current control to be up to 1ampere. I think this will be better option instead of searching for opamp above 40V...

[exe]

There is no "perfect" circuit. I suggest read through a few discussions about lm723, then make your judgement what's better for you.

Getting a good performance power supply is challenging and requires research and understanding. So, if you want to get a good knowledge about power supplies be prepared to spend months on reading and experimenting. I suggest do not blindly copy someones design as there are plenty of bad designs on the net. It's also easy to make a mistake while assembling it. Fixing mistakes is very hard without understanding how things should work. I'd also challenge your specification. You want 36V, what for? May be building two floating 18V regulators is easier, so you can chain them into 36V when needed, or put them in parallel and get 18V at double current. Or may be you need a bipolar supply... So, even making a useful and realistic specs requires a lot of thinking.

I can suggest reading this thread because there are many reputable people there: https://www.eevblog.com/forum/projects/good-quality-lm723-lab-power-supply/25/ . If you are not bound to lm723, then I'd do this power supply: https://www.eevblog.com/forum/beginners/how-does-blackdog_s-psu-work/ . I've been using this PSU for years, it works well for me: https://www.eevblog.com/forum/beginners/please-critique-this-linear-psu/ (it needs a diode accross one cap in capacitor multiplier, and has high temperature drift due voltage ref circuit, but still usable).

In any case, working with mains is dangerous, a mistake in a circuit can set your house on fire, or even kill. Please be careful. It might be better start with learning about safety.

[exe]

After some thinking, I highly recommend buy a two-channel lab power supply, and use it to supply your circuits. You also need at least two dmms, a two-channel oscilloscope. Start with building a power supply from two lm317.  In the datasheet there is a circuit like this one: https://www.eevblog.com/forum/projects/lm317-_labratory_-power-supply/ . It should be enough to start. Put lm317 on  do some math ), be sure they are isolated from each other. Oh, and read the datasheet of course!

[BravoV]

Save your breath guy, this kind of thread with this particular people from the region always change their requirement, based on what are available in hand but has no clue about electronics nor initiative to learn, and worst keeps nagging.

Its like ... "I own a pipe from scrapyard and a screwdriver .... can somebody help me to make a big cannon gun like the one used in tank ? Please Sir !" 

We have countless of this similar request alone in this forum, and ended up abandoned.

[rao]

Thank you bravo... For your guidance through out this thread...

[MK14]

Thank you bravo... For your guidance through out this thread...

Talking about GUIDANCE.

Threads could do with GUIDANCE, as to exactly what they are about (Descriptive Title, and useful/detailed opening post(s) ).

You still don't seem to have specified, what you are trying to do, what help you need (if any), and what resources are available to you.
You have to some extent, done the above, but the details keep on changing, all the time. Making it rather difficult for anyone to help you.

[BravoV]

I HAVE TO WORK FOR MY LIVELIHOOD, SO I DIDNT FIND TIME GO TO MARKET AND SEARCH FOR ICS.

Thank you bravo... For your guidance through out this thread...

Good, finally I've contributed significantly to your life and made you realized, go, go keep working for your life 1st, delay the tinkering with electronics until one days in the future, this hobby will become more affordable to you.

And NO, you just can not keep nagging and whining people to supply you with a working schematic, with just 741 op-amp or 723 chip ... or what ever cheap components you could find in your drawer or junk yards with that high requirement of yours, again, read my analogy above on making military tank's cannon.

Its like you ONLY have flour powder (atta) and water, and only can make "roti" (Indian very basic common peasant's bread/dough), and somehow you want us to help you to make a full fledged and rich Italian pizza with various luxury toppings, that is impossible, no matter how hard you nag.

vs

[rao]

Sorry all,

With in two  month, my specification has changed 3 times. I bought two transformer.
Now I decided to construct rps from second transformer 26V@5Amps...learned the difference between smps and linear power supply. Smps will be suitable for high power because series element will be present in on conditions depending up on duty cycle.. I bought L296. I dropped that because I could not control voltage and current .

Finally I came through lm723 which do voltage and current regulations.

Myself has learned all this from this forum and no were else...

I thank all of them...for their help.... Thank you all...