I'm trying to design a fob-chip combination, where the very small chip can be placed in an object and have a fob with a button that will make the object beep every time the button is pushed.
Anyone have any suggestions regarding microchip and where to acquire them? I have been searching google for ideas but I haven't been able to find exactly what I want. Most posts are related to pet chips, and the chip would work (they are small emough) but they never mention anything about a fob that could make the chip beep.

It is essentially a locator chip/device to help find lost items.

 

What range?

What frequency?

What power source?

How small?

Note that the receiver must be powered on continuously. Also, there are specific frequency bands reserved for functions such as this, and those frequencies have minimum antenna dimensions for normal operation. Of course you can use a smaller-than-optimal antenna size, but that will drastically decrease the operating range.

To get a feel for the size of commercially available units, search for RF remote control modules on ebay. They are very low cost, but probably larger than you want.

ak

https://www.ebay.com/itm/3948169363...5Lx7LgDIlyZlod2Kk83Neq/6I=|tkp:Bk9SR6iBks3HYg

 

Range would need to be roughly 100-200 meters, I have no idea about frequency (pretty new to this and looking at options), power source I was hoping a watch battery in the fob would do the trick but again I'm new to this stuff and not sure.
It needs to be as small as absolutely possible, so as to not negatively affect the objects structurally

 

I'm trying to design a fob-chip combination, where the very small chip can be placed in an object and have a fob with a button that will make the object beep every time the button is pushed.
Anyone have any suggestions regarding microchip and where to acquire them? I have been searching google for ideas but I haven't been able to find exactly what I want. Most posts are related to pet chips, and the chip would work (they are small emough) but they never mention anything about a fob that could make the chip beep.

It is essentially a locator chip/device to help find lost items.

Welcome to AAC.

It is a clue that what you are asking for is not already available. You are facing several problems.

1. Power Source
You will have to power both a receiver and audible annunciator. The receiver is easier than the sounder. But you will still need something “large” for the receiver. Practically, this means a coin cell, or a small LiPo cell (~10mm x 20mm). So that’s already a large component. You also couldn’t embed the device in a way that it was inaccessible since the battery will need changing.

The sounding device will require much more current than the receiver if you want it to be audible for 200m. This means if the device is actually used, the battery life will be very short.

2. Antenna
The receiver will need an antenna. This will require a fairly large area, bigger of smaller depending upon the operating band you select. Normally, this is scaled to fit the case that has to hold both the battery and sounder.

3. (Possibly) A Misunderstanding
Since you mentioned “microchips” and referred to the sort of “chip” put in a put for RFID, I think you may misunderstand what a “microchip” would be in your scenario. Your device would have to use a printed circuit board (PCB) to hold at least one chip along with several passive components and possibly active components.

A radio frequency identification (RFID) tag or chip is powered by a radio transmitter that is held close (much closer than 200m) to the device. The received signal is turned into power which causes the chip to transmit a small signal with digital information on it. It is nowhere near enough power to make a useful sound.

I would suggest you look at the commercial offerings (such as Tile, and Apple AirTags) that do what you want. The difference is that they use bluetooth, and AirTags also provide location information. But they are very little different than what you are asking for, and the size is about what will need.

 

Range would need to be roughly 100-200 meters,

I was hoping a watch battery in the fob would do the trick

Nope x 2.

1. 200 m is way beyond the reliable range of typical RF applications, such as remote controls, WiFi, garage door openers, etc, because of limitations on both the xmtr and rcvr.

2. The battery in most fobs is much larger than a watch battery, and still is *way* less than what is needed for 200 m range.

In case you're wondering, the reason a small cell phone can reach 2-3 miles is because a) it has larger batteries and antennas than you can tolerate; and b) the other end of the link is a hundreds-watt transmitter, very large antenna, and a sophisticated, specialized receiver up on a tower. All four of those things are needed for range. A cell phone is deceptively small because the other end of the link is huge.

A better comparison might be FRS walkie-talkies. Even if you strip down the two units so that one is transmit-only and the other is receive-only, and that reduced the unit volume by, say, 33%, that still leaves a pretty big lumps of stuff to do what you want to do.

ak

 

The fob size is really irrelevant as I would be holding it my hand, range is maybe overstated, I would have a rough estimate of where the object that I want to put it in is, but it would need to start "beeping" as I approached...maybe even 20 meters...
and the "chip" that would be in the object would need to be very small so as not to change the weight, shape of the object.

For instance, I have a ball (with the chip) I throw it a distance, and as I walk to where I threw it I could start pushing a button and the ball would start beeping.

would the chip in the ball need a power source, or would the fob only need it? That's originally why I was thinking something along the lines of a pet chip locator? I don't want to use something as complicated as a GPS type unit...I don't want to be reliant on having my phone in hand, and phone signal, etc...

 

20 m is much more doable, and within the range of some key fob systems. But still . . .

A pet chip works similarly to a wireless charging system - the scanner radiates an electric field that is strong enough to power the chip when it is very close. And, the chip is responding at a much lower power level than even the smallest beeper needs. Radiating enough energy to power a beeper at 20 m almost certainly is not legal. That means that the receiver must be battery powered.

ak

 

Chips do not beep. Chips can make an audio transducer beep.

Take your phone, find a beep sound, then see how well you can locate it 20m. If the environment is noisy, I expect that you will not be able to hear it. It is going to have to be pretty loud for this, and loud requires power. I would say that, minimally you are talking about a board that is about 1 in^2 and a transducer the same size and a battery similar in size. Maybe doable in a 1 x 1 x 1/2 inch package. And that is with a custom designed board. If you use available modules there will probably be 3 of them each of about that size.

Far simpler would be a bluetooth transceiver that talks to your phone. Oh, wait, you can buy that ready made.

 

Chips do not beep. Chips can make an audio transducer beep.

Take your phone, find a beep sound, then see how well you can locate it 20m. If the environment is noisy, I expect that you will not be able to hear it. It is going to have to be pretty loud for this, and loud requires power. I would say that, minimally you are talking about a board that is about 1 in^2 and a transducer the same size and a battery similar in size. Maybe doable in a 1 x 1 x 1/2 inch package. And that is with a custom designed board. If you use available modules there will probably be 3 of them each of about that size.

Far simpler would be a bluetooth transceiver that talks to your phone. Oh, wait, you can buy that ready made.

If the handheld piece is what beeps as I approach the object/ball that would be fine, but I still need to know what kind of chip I would need or could use??

 

Whether the ball/object beeps or and handheld fob/device beeps on approach is irrelevant...either would work. I will have a general idea of where the ball is, but want to be able to pin point where it is as I get closer.

Is there a chip small enough (<10mm) that would work? maybe it connects via bluetooth, maybe some other method...but it would need to be able to sync up with the device for repeated usage, or to a second ball/object if the first one is completely lost.

 

How can I say it that you will understand?

It is not a chip that you need, it is a complete system, including a bluetooth transceiver, a microcontroller, and a battery.

You can find a bluetooth module ( a chip plus additional components plus an antenna) that is about 1cm in size. But all that gives you is a communication link, something has to listen and talk over that link. That is the microcontroller. It would listen for a call from phone, and respond saying it heard it. It would be best if you had a custom board that integrated all both of those parts, but you are nowhere near capable of making that.

And if you think you can come up with something cheaper than a commercial product, you are delusional. Those are produced in quantities where they they can get the parts fit 1/10 if what they will cost you.

 

I have no illusions of being able to produce this on my own, I am aware that I would need to purchase it.
I just have no idea where to start and who to contact or enlist.

Hypothetically, if I am committed to having to buy the entire system...does this exist?
I need something very small that will fit inside a ball (let's say a ball with 2-in diameter), and a handheld device that can beep as I approach the ball when a button is pushed?? Would the transceiver go in the ball? (that's what I am understanding); the microcontroller and battery would be in the handheld part?

 

I guess you missed it where someone suggested tracking tiles or air tags. Those are the commercial products I know of. There are probably much cheaper Chinese versions.

 

I am just repeating what I already said, but you didn’t respond so maybe you missed it.

You simply can’t do what you want. The minimal reasonable size for what you are describing is going to be about the size of an Apple AirTag or a Tile. They are versions of what you want.

The biggest problems are the power source, the transducer that will be the sounder, and the antenna. These all have a minimum size that is much bigger than what you are asking for.

At a minimum, you will need something the size of a CR2032 lithium coin cell which is 20mm φ and 3.2mm thick—and it will have to be accessible for changes, or you will need something like a 402025 LiPo cell which is 25 x 20mm and 4 mm thick, and you will have to have some way to charge it that is accessible.

​

The sounder has lower limits on size because it has to move enough air to make an audible signal. Piezo buzzers are usually used for such applications. They require a resonant chamber to let increase the audible output. The smaller the diameter of the piezo the taller the chamber as to be.

A typical version designed for surface mounting that might be loud enough to do any good at all would be 8.7 x 8.7mm and ~3mm thick. It also has a port on the side that has to be able to interact with some air.

​

The antenna also has a lower size limit dictated by physics. A minimalist PCB antenna for the likely band you would want to use is going to tun about 26 x 22mm and ~1.5mm thick.

​

And, you will need a printed circuit board (PCB) to hold the components that will comprise the radio receiver or transceiver, the various passive components needed, and the piezo buzzer shown above.

I hope you can see that your idea just isn‘t practical, unfortunately. It would be nice if such things were available.

 

I have no illusions of being able to produce this on my own, I am aware that I would need to purchase it.

How does this not contradict your original post?

I'm trying to design a fob-chip combination

 

well I need to buy the pieces, and put them together, I can't physically create any of the individual pieces.
Just wanted to know if components existed that would work if I was able to combine them, or have someone combine them.

 

well I need to buy the pieces, and put them together, I can't physically create any of the individual pieces.
Just wanted to know if components existed that would work if I was able to combine them, or have someone combine them.

So you are just purposely ignoring my posts?

 

So you are just purposely ignoring my posts?

No, I read it. But I needed to respond to everyone else aswell...

 

well I need to buy the pieces, and put them together, I can't physically create any of the individual pieces.
Just wanted to know if components existed that would work if I was able to combine them, or have someone combine them.

It is really depressing to think that anyone thinks that what we do is that simple.

 

No, I read it. But I needed to respond to everyone else aswell...

But I answered the question you said you had, in detail, and you didn’t respond to me at all.