IR Receivers: Hoarding Time!
erco
Posts: 20,256
I've been searching for a while, and finally found this jewel at Mouser: Vishay's TSOP4038, a special little IR receiver that is "continuous signal compatible". The data sheet says it will even detect an unmodulated 38 kHz signal like the old Sharp 40KHz tin cube sensors would. You're probably yawning already, but believe me, they are RARE. And very useful for IR beacon tracking. Most IR modules can't detect a constant 38 kHz signal for more than a second or two (including the ones that come with Boebot, unfortunately). Try it and see for yourself...
Anyway, I'm stocking up for a variety of reasons. I'm doing some beacon experiments in ROBOT magazine; they're cheap at 78 cents each; and finally, they may be going away soon, the datasheet says "not for new designs".
http://www.mouser.com/ProductDetail/Vishay/TSOP4038/?qs=%2fha2pyFaduj0SkmO2XfIrLlK1mhOELebdZ0wsDRU2VQ%3d
Datasheet at http://www.vishay.com/docs/81926/tsop4038.pdf
You haven't heard the last of me on beacon tracking, BTW.
Anyway, I'm stocking up for a variety of reasons. I'm doing some beacon experiments in ROBOT magazine; they're cheap at 78 cents each; and finally, they may be going away soon, the datasheet says "not for new designs".
http://www.mouser.com/ProductDetail/Vishay/TSOP4038/?qs=%2fha2pyFaduj0SkmO2XfIrLlK1mhOELebdZ0wsDRU2VQ%3d
Datasheet at http://www.vishay.com/docs/81926/tsop4038.pdf
You haven't heard the last of me on beacon tracking, BTW.
Comments
The datasheet says it can also handle 38 kHz bursts. Does this mean it could be used in place of detector Parallax sells?
Precisely! A 556 dual timer makes a perfect cheap & easy beacon, half generating the 38 kHz carrier and the other half modulating it at 800-1000 hz. But most IR receivers filter out any regular modulation like that. If you want to, you can add a micro to a beacon and pulse out Sony codes to almost any IR receiver, but that's more complicated & expensive, and it takes longer to decode. Simpler & faster is better in my book. With this receiver, you could have dozens of beacons all over your house, each modulated at its own unique frequency so even a BS2-based robot can tell them apart in 10 milliseconds.
This particular receiver is the rare bird that can also detect an unmodulated 38 khz signal, so if you want to simplify further, your beacon could just be a 555 timer. Those of course, all look identical to the receiver.
Yes, it should function to receive standard Sony IR codes and such. But it may be more susceptible to noise and sunlight since it lacks some of the filtering that other receivers have. Will advise when I get 'em in.
For general remote control applications, I think the TSOP38238 might get the nod, and it's applicable to the Sony's as well.
-- Gordon
http://www.radioshack.com/product/index.jsp?productId=2049727 Yep, that's my review: BUSTED!
-- Gordon
They may have another advantage over other sensors, the ability to swag distance, per http://www.vishay.com/company/press/releases/2010/100628irsensors :
Many other applications require a reflective sensor that detects not only presence but also proximity by measuring the strength or weakness of the reflected signal. Instead of a fixed detection threshold, analog information from the sensor is needed. This is possible with the TSOP4038, TSOP58038, and TSOP58P38 IR proximity sensors. The length of the sensor’s output pulse in response to the emitter signal varies in proportion to the amount of light reflected from the object being detected. For near objects, the output pulse approaches 100 % of the emitted pulse, for far objects the output pulse becomes shorter.
Anyway, I just went to order some more TSOP4038's from Mouser, and stock is zero and obsolete. I am contacting the companies that have them in stock, and I wanted to see if any one wants to do a group buy?
I am waiting on a stock quote from one company right now.
You know me, I'm down for a hundred. Where from, Jim?
I'm trying Solarbotics first:
https://solarbotics.com/product/TSOP4038/
Allieded has 35 that can ship in 8-10 days:
http://www.alliedelec.com/search/productdetail.aspx?SKU=R1084633&utm_source=FindChips&utm_medium=buyNow
Farnell Element12 Asia has 3222 in stock.
Thanks Ron,
Worth checking into.
These IR receivers caused a product launch failure for me. They switched the component from a 5V component to a 3.3 -> 5V component without changing the part number. It cost me a serious 4-figure loss of money and reputational damage.
Here's the response I got from Vishay:
Be very careful buying stock of Vishay parts.
The published datasheet says 3.3v -> 5v, the parts you get sold may be 5V parts.
Thanks for that update.
So the parts you received were 5V parts and would not work in your 3.3V application. Did your supplier ever come clean?
Somebody did, Gordon!
So are you still sitting on these parts? You may be able to sell a lot here.
Jim
I just bought more TSOP4038s than I need from Solarbotics. Please don't tell the wifey!
If you want some, PM me. Our friendly Canadian neighbors gouge considerably on shipping and handling on small quantities.
Jim? Whit? Duane? Mike? Martin? Rich? I'm counting on you boys to bail me out!
The latest data sheet says this
Not for New Design - Alternative Available: New TSSP4038 (#82458)
and that replacement TSSP4038 looks to be more widely available. at Element 14, Future & Digikey
Of course Murphy's law says that continual design (25m) has a different pin out from the NEC AGC pulsed one I just chose...(TSOP2438, 45m) and the other pin version (TSOP4438) is less available...
Rich
Thanks for that info. The spec sheets look pretty similar.
Supplier blamed the vendor. Vendor blamed the supplier. I nearly lose my shirt over it.
I won't use either again.
I'm not bitter towards IR and have moved to RF.
I can now get bi-directional RF up to 300kbps between devices (P2P or broadcast) with a potential range of a half-mile for about the same price as RF. It just needed a driver written... and that's pretty close to done :-)
Sorry for the slight topic detour.
The moron that created a situation where one part number can apply to two distinct and incompatible items should have been sacked.
How many do you need to get rid of?
'Bout a hundred. I bought way too many to get free ship. Might take a while to sell, but I may eventually use 'em all up myself. I'm doing some contract work now and there is amazing demand for localization, beacon tracking, and return to charger apps.
These are rare "continuous signal compatible" types, but they also work great for standard IR control, like Sony codes etc . And as I mentioned previously:
These have another advantage over other sensors, the ability to swag distance, per http://www.vishay.com/company/press/releases/2010/100628irsensors :
Many other applications require a reflective sensor that detects not only presence but also proximity by measuring the strength or weakness of the reflected signal. Instead of a fixed detection threshold, analog information from the sensor is needed. This is possible with the TSOP4038, TSOP58038, and TSOP58P38 IR proximity sensors. The length of the sensor’s output pulse in response to the emitter signal varies in proportion to the amount of light reflected from the object being detected. For near objects, the output pulse approaches 100 % of the emitted pulse, for far objects the output pulse becomes shorter.