# Voltage sensing options

I would like to see all options available for voltage sensing (e.g. Voltage dividers, dedicated ICs etc.) I'm mainly interested in ICs that can do voltage sensing with minimal losses to the main circuit. The voltage range is going to be from 0-50V and the current will be from 0-6A.

I would like to see all options available for voltage sensing...

Since you know enough about voltage sensing to name a few examples, you need to perform your own research... This is not a lexisnexis kind of place!

If your research brings you back to needing to integrate a chosen sensor or circuit with a specific Arduino, the forum can likely help. Read the forum rules (stickies) first before you repost in the future.

Ray

Ray,

I have done my research and am exploring the possibilities of dedicated ICs for voltage sensing. I've noticed that this forum is for project guidance. Allow me to refresh your memory on the definition of guidance. Guidance is the act or function of guiding; leadership; direction.

I am seeking guidance on which IC to use for the range of voltage stated in the original post.

Yes, but you asked for -all- options. A bit of a tall order, quite a lot to expect someone to type into a forum message.

Voltage sensing with minimal loss. You haven't defined what "minimal loss" is, but it sounds like you need something high impedance. Is that DC voltage and current? A resistive voltage divider seems the simplest way. If you are using the Arduino's ADC, it works best with a resistance of 10k or less. However, for a voltage divider, that is the Thevenin equivalent resistance. So if, say, 260uA is a minimal load (I would guess it is in a 6A circuit), a 10k and a 180k resistor will drop 50V down to about 2.6V for the Arduino's input while still presenting the Arduino's analog input with a tiny bit less than 10k.

You'll want a couple of protection diodes to prevent the input from going much above 5V or below ground. A couple of fast 1N914 diodes will do, although with 180k feeding it, you are probably find with the internal protection diodes in the microcontroller.

"But Polymorph, what about 5V? Why can't I drop it to 5V for maximum ADC resolution?"

You can, use 10k and 91k and it will drop 50V down to about 4.95V.

Allow me to refresh your memory on the definition of guidance. Guidance is the act or function of guiding; leadership; direction.

Yes. But the full-path is: Arduino Forum::Using Arduino::Project Guidance

You completely omitted any reference or suggestion to how an Arduino would be incorporated. Perhaps in the future you will try your hand at answering queries in the Forum. About one in ten times you will run up on sarcasm such as your "Allow me to ..." statement. Such statements keep many knowledgeable members from engaging in the help process because they are intimidated by such responses.

Ray

Not any ICs I can think of that allow direct measurement of 50 vdc. What is usually done is to scale the voltage down via resistor dividers to a range the ADC can handle and then rescale the voltage range in software. A lot depends on what resolution and accuracy requirements you have. The build in analog pins on arduino boards are somewhat limited as it's just a 10 bit ADC and general recommended source driving impedance is 10K ohms or less. However there are tons of small inexpensive I2C or SPI ADC modules available in just about any resolution required. However none will handle more then the common Vcc voltage levels of 3.3vdc or 5vdc maximum input voltage.

If you've done your research let's see it. Don't say you've done ANY research unless you are going to post the information that you found. We get dozen's of people posting every day who CLAIM to have spent hours, days , weeks looking and the net with no success and their question is almost always something anyone can find in 2 seconds on the net. Talk is cheap. Show your work or don't make any claims to have done any research. If you had done ANY research you would know that if you want to measure dc in the range of 50 V you can use a voltage divider and an op amp voltage follower. As Ray pointed out. We are not here to gather information for you. You have to do your own research. If you want any help you need to learn some manners. You have a lot of nerve to come here asking us to do your research and then lecture Mr. Burnette on the definition of guidance. SHAME ! FACE PALM ! If you want any help on this forum don't do that again.

Thanks retrolefty, I simulted the system in simulink and PSpice to see what values I would be seeing at the output of the voltage divider circuit. This was to make sure I wouldn’t fry the arduino. I was just hoping there would be an IC that could do that instead.

raschemmel,
I was inquiring on voltage sensing ICs. the current method I am using is stepping down the voltage by a factor of 10 via a voltage divider. This is because 50/10 = 5 which is the sensing range for the arduino. This is a basic concept hence why I was inquiring about ICs. I’m glad you were able to stroke your ego as a white night of the forum raschemmel. posters such as yourself are the reasons I choose not to answer anything on this forum. Why would I bother giving advice when I now know that the correct response to all inquiries is to chastise them based on the assumption that they haven’t done any work.

impactblu:
, I choose not to answer anything on this forum.

sorry to not want to do any research…

there is a word I am looking for…

@impactblu, No need to get all huffy. If you're innocent then I was not talking about you. I simply said if you did some research, then post it. A normal response would be " I did my research and here it is.." without getting all bent out of shape. Most member post asking a question and say " I am looking for ways to sense voltage. I found these links .. can you suggest anything better ?" and post the links. The thing you have to remember about posting on a forum that has so many experts is that they can see through BS, which we get a lot here. I objected to your "I would like to see etc etc " manner of requesting information like we are here just to find it for you. We are here to answer questions. You didn't ask any. You simply demanded information. If you asked "What is the best way to..." we would have gladly answered your question. I am not a white knight. Far from it.In fact, if you took a vote it would probably be 8-2 in favor of Black Knight. I have incurred the wrath of more than one poster because of my direct approach. If you were polite, I would have been polite back. Posting on a forum of experts and asking them to present ALL THE WAYS TO DO SOMETHING is asking a bit much , don't you think ? You might start with a single question and then work from there, but to demand an entire research package is presumptuous at the least. If you want to redeem yourself you can post the " "research" that you did.

About one in ten times you will run up on sarcasm such as your "Allow me to ..." statement. Such statements keep many knowledgeable members from engaging in the help process because they are intimidated by such responses.

I am not easily intimidated. My suggestion to you is in the future, show a little respect to the experts you are consulting and try a little humility, (instead of the "Allow me to ..." approach).

maybe I did not understand the question fully.

to re-phrase:

"I have already tried multiple ways to measure voltage, IC's, voltage dividers, etc. I have run some SPICE models and am not satisfied with what I have come up with.

you are commanded to list all possible ways to measure voltage so that I may discard any ways that I have already tried and see if you have come up with anything I did not."

does that about sum it up ?

Well put.