Author Topic: Does anyone know how I can get a value from this? (Read 7542 times)

Hawaii00000 · « **on:** April 04, 2009, 05:13:31 PM »

I have one of these ( http://hueyjann.manufacturer.globalsources.com/si/6008814971720/pdtl/Photodiode/1001325624/3-Pin-Photodiodes.htm ) that detects infrared light and I need to know how I'd wire it to get a value from it. I'm trying to make an ir range finder out of it.

SmAsH · « **Reply #1 on:** April 04, 2009, 05:19:55 PM »

to wire it up if you have the side with the bubble facing you and the legs poking out to the right from top to bottom:
|---------|---------signal
| (-) |---------gnd
|---------|---------vcc man that took a while to get right lol. here you go. just in future check the data sheet first before asking. if you cant find em google the part number data sheet http://akamai.globalsources.com.edgesuite.net/f/593/3445/5d/pdt.static.globalsources.com/IMAGES/PDT/SPEC/624/K1001325624.pdf

Hawaii00000 · « **Reply #2 on:** April 04, 2009, 06:14:03 PM »

Most of these work on about 5v, right?

SmAsH · « **Reply #3 on:** April 04, 2009, 06:19:02 PM »

Quote from: website on April 04, 2009, 06:14:03 PM

Key Specifications/Special Features:
* IR receiver pre-amp module (IR2638)
* IR receiver pre-amp module for remote control, TV, home applications
* Feature: small type, 3-pin
* Supply voltage: 4.5 to 5.5V
* Please refer to Huey Jann's catalogue on pages 11

read the page silly.

Hawaii00000 · « **Reply #4 on:** April 04, 2009, 06:38:51 PM »

oh I get it! I didn't know how ready the thing. I did look at it.

SmAsH · « **Reply #5 on:** April 04, 2009, 06:47:02 PM »

hehe, are you just trying to make something that can go 'oop wall over there dont know how far tho' or do you want yours to be able to tell distance?

Hawaii00000 · « **Reply #6 on:** April 04, 2009, 08:04:56 PM »

Probably more of the " 'oop wall over there" one.

SmAsH · « **Reply #7 on:** April 04, 2009, 08:10:53 PM »

so its like a non-contact bumper switch?

Hawaii00000 · « **Reply #8 on:** April 04, 2009, 08:16:21 PM »

Actually now that I think about, it it does have to have to be able to measure distance to some degree. It just doesn't have to be mega accurate. Its going to be running a program like the one that Stampy does; the one where it follow what's in front of it.

SmAsH · « **Reply #9 on:** April 04, 2009, 10:55:43 PM »

that may be hard to do as an ir rangefinder has complicated electronics in it that allow it to measure an angle. at least i think they do?

Metal Slug 2 · « **Reply #10 on:** April 04, 2009, 11:22:25 PM »

why not just purchase an IR rangefinder or sonar? check this out:

http://www.societyofrobots.com/robotforum/index.php?topic=968.0

SmAsH · « **Reply #11 on:** April 04, 2009, 11:23:25 PM »

i figured that would be a bit more expensive but way easier to connect/start running.

bionic-man · « **Reply #12 on:** April 04, 2009, 11:34:38 PM »

Hawaii00000, how were you going to wire this thing? schematics?

SmAsH · « **Reply #13 on:** April 04, 2009, 11:46:46 PM »

probably something like this perhaps? http://www.societyofrobots.com/schematics_infraredemitdet.shtml

Metal Slug 2 · « **Reply #14 on:** April 05, 2009, 12:41:35 PM »

Quote from: SmAsH on April 04, 2009, 11:23:25 PM

i figured that would be a bit more expensive but way easier to connect/start running.

based on what Hawaii00000 wants to do ( 'oop wall over there' , lets go a different direction...sorta thing) a IR rangefinder or better (for this purpose), a sonar would be ideal. You can find Sharp IR rangefinders from as little as ~$9 (USD) and a sonar from about ~$25.

cheak out these sites:

http://www.roboticsconnection.com/c-4-robot-sensors.aspx
look for GP2D120 or GP2D12

http://www.sparkfun.com/commerce/product_info.php?products_id=8959
this would probably be the best for your bot in terms of ir rangefinders

for a sonar rangefinder, check this out:

http://www.parallax.com/Store/Sensors/ObjectDetection/tabid/176/ProductID/92/List/1/Default.aspx?SortField=ProductName,ProductName

Hawaii00000 · « **Reply #15 on:** April 05, 2009, 07:43:06 PM »

The only reason I'm doing it this way is because I already have the parts. Unfortunately it starting to get frustrating, because I'm getting so weird readings.

Hawaii00000 · « **Reply #16 on:** April 05, 2009, 07:49:44 PM »

Can you guy help me out? I programed it to turn on an led when the level when below 810 and the wire signal is in an analog. It worked perfectly at first, but it started reading positive all the time, then it would switch back to normal. AND it still worked when I covered the sensor!!!!!!!!

SmAsH · « **Reply #17 on:** April 06, 2009, 01:21:02 AM »

have you tried it in the dark as ambient light may affect it?
have you tried replacing components? checked orientation of your components?

paulstreats · « **Reply #18 on:** April 06, 2009, 11:43:58 AM »

how do you have it wired? (again)

do you have its output wired directly to the analog input?

SmAsH · « **Reply #19 on:** April 06, 2009, 01:58:03 PM »

|---------|---------signal
| (-) |---------gnd
|---------|---------vcc as i said, gnd is wired to common gnd, vcc is +5V and signal is to a pin on your mcu.

paulstreats · « **Reply #20 on:** April 06, 2009, 05:14:15 PM »

is that how you have it wired or is that how the OP has it wired? either way there needs to ba a potential divider stage before it goes to the microcontroller.

(I wasnt asking for the pinouts I was asking how he actually had it connected. Connecting straight to an adc wouldnt produce a real reading).

The page where you linked to also mentions other devices for amplifying the signal, are these definately present on the device?

Razor Concepts · « **Reply #21 on:** April 06, 2009, 05:20:28 PM »

Are we sure that has an analog out?

Hawaii00000 · « **Reply #22 on:** April 06, 2009, 10:17:26 PM »

Quote

have you tried it in the dark as ambient light may affect it?

yep

Quote

have you tried replacing components?

Unfortunately I don't have any replacements right now.

Quote

checked orientation of your components?

I think its right, but maybe I should check.

Quote

is that how you have it wired or is that how the OP has it wired? either way there needs to ba a potential divider stage before it goes to the microcontroller.

Could you explain or maybe give ma a link? Right now its just connected straight to the board.

The weird thing is that WAS working, but I covered it up and it STILL worked.

Then it just went crazy and alway read positive.

paulstreats · « **Reply #23 on:** April 08, 2009, 09:09:33 AM »

Quote

The weird thing is that WAS working, but I covered it up and it STILL worked.

It might have just been a noisy signal or other interference lulling you into believing that it was working....

To connect it for reading variable voltages is easy. Just place a resistor between the photodiode output and gnd. the connection to the analog pin should come from between the photodiode output and the resistor. You could use a potentiometer instead of a resistor so you can vary the output.

If you find the output is too low like this, you might have to use a transistor too but I think that photoresistor has an internal amplifier.

You can do the sums to find the best resistor for the job but a general 1k2 resistor should give you some resolution of results. A potentiometer again would let you manually calibrate the output.

Hawaii00000 · « **Reply #24 on:** April 08, 2009, 11:18:44 PM »

Ok I'll give it a try and report back it a day or two.

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Author Topic: Does anyone know how I can get a value from this? (Read 7542 times)

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