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Im abit confuse how to i connect my supply to my opamp Vcc.
Should i do it by method a) or b). The last time i used the opamp i happen to fry it due to wrong Vcc wiring. I must get it right this time
I assume you are using the 741 op amp. Well, both are wrong. The 741 is a dual supply opamp. If you are using 15V supplies, you'll need 2 of them.
Opamp V+ is connected to the +VE of Supply1.
Opamp V- is connected to the -VE of Supply2.
-VE of Supply 1 is connected to +VE of Supply2.
Hi Fabbie,
The polarities of your supplies are correct now, but I don't think an old 741 opamp will work with only 10V across it. Use a more modern opamp that can work with either a single supply of 3V to 44V, or dual supplies of 1.5V to 22V.
Is correct.
A 741 op amp will work on a sngle polarity 9V supply depending on it's use. All that is necessary is to bias one input to 1/2 the Vcc voltage with
a voltage divider.
Hi Fabbie,
I said that I didn't think that a 741 will work with 10V across it, which is dual 5V supplies like you show.
It is rated for use only with dual 15V supplies where its output has a voltage loss of up to 5V positive and 5V negative when driving a load resistance of 2K or less. With dual 5V supplies its output might not have any output voltage swing whatsoever.
Its input common mode range has a limit of 3V from each supply, so with dual 5V supplies might have an input voltage swing of only positive 2V and negative 2V, which isn't much.
You could test one and it may work or not. You could test ten and some might work and others not. If you want them all to work then select an opamp that is designed for your low-supply-voltage application.
Alright, THX audioguru. I'll keep that in mind.
I tested the 741 by applying a non-inverting opamp with a DC input of 1.5V and gain of 2. I used 5V and -5V for my Vcc and i achieved good results which was 3V.
just a small suggestion if you want to upgrade your op-amp design goto www.ti.com it's the texas instruments website, once there look up a OPA2134 these are precision op-amps that come in single dual and quadruple packages. These things work insanely better than a 741. The neat part is that you can overnight samples for free, i did this lots of time when I tried to build my guitar pre-amp. There's a max to how many you can order but it's better than paying $100 for a thousand.
I have an irrelevant question. But, it needs to be answered, for, it has kept me up at night several times. I have spent hours puzzling over this question and it needs answering to. This question can also cause other people to be confused. But anyway, here goes:
I don't understand how people are "Electronic God" or "Electronic Expert" or "Electronic Oracle". How are you a God of electronics? Is that not a sin, to be a god? My opinion of this site is becoming more unholy.
I have an irrelevant question. But, it needs to be answered, for, it has kept me up at night several times. I have spent hours puzzling over this question and it needs answering to. This question can also cause other people to be confused. But anyway, here goes:
I don't understand how people are "Electronic God" or "Electronic Expert" or "Electronic Oracle". How are you a God of electronics? Is that not a sin, to be a god? My opinion of this site is becoming more unholy.
Actually, I wanted to be called "Grand Poobah of Electronics", but apparently it was taken. I had to settle for god. I'm a little miffed that there are more than one of us.
I don't understand how people are "Electronic God" or "Electronic Expert" or "Electronic Oracle". How are you a God of electronics? Is that not a sin, to be a god? My opinion of this site is becoming more unholy.
I just wan to confirm this.
If i input +5V into my +Vcc and GND my -Vcc, it wouldnt change my maximum opamp output, right? The only difference would be the opamp wont be able to output out any negative voltage, right?
My opamp purpose is only to generate a positive output, therefore, i might no need a -5V into my -Vcc.
I just wan to confirm this.
If i input +5V into my +Vcc and GND my -Vcc, it wouldnt change my maximum opamp output, right? The only difference would be the opamp wont be able to output out any negative voltage, right?
My opamp purpose is only to generate a positive output, therefore, i might no need a -5V into my -Vcc.
As long as you choose a suitable opamp, which must work off a single 5V supply, accept inputs to either supply rail, and provide outputs to either supply rail.
As I've previously mentioned, I used a 2.5V reference, and a split supply, in my A2D tutorial - simply to make the choice of opamp far easier.
Since i intend to output ONLY a positive value from my opamp, i was thinking if it was possible NOT to use a voltage converter for my -Vcc. Of course the best way is to a split supply. Howver, if it were possible to GND the -Vcc and get my desired positive output, i would prefer to do that since it would plenty of resources(money,time, PCB space)
Wow, to be honest with you...I'm surprised. Being a "God" only takes the person the effort of posting a lot of posts? So, in order for me to become a "God," all I have to do is to post a lot of posts. But, that title can be false then. If someone just posts many replies, but doesn't actually know that much about technology, wouldn't that be a false title.
Wow, to be honest with you...I'm surprised. Being a "God" only takes the person the effort of posting a lot of posts? So, in order for me to become a "God," all I have to do is to post a lot of posts. But, that title can be false then. If someone just posts many replies, but doesn't actually know that much about technology, wouldn't that be a false title.
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