IR Receiver for 3.3v

Forum 2005-2010 (read only) Hardware Interfacing
1

I'm working with an IR receiver (TSOP2138, datasheet.octopart.com/TSOP2138-Vishay-datasheet-58051.pdf) which seems to work on the 5v Duemilanove but not with the 3.3v Pro Mini.

My best guesses as to the problem:

Voltage - The receiver won't work with 3.3v. According to the datasheet it should be fine but I'm probably missing something.

Output - I don't have a very firm grasp on how this all works. If I feed it 3.3v is the ouput signal going to be 3.3v? Or is it 5v and I need to do some logic level converting?

Processing Speed - The Duemilanove has the ATmega328 running at 16MHz, the Pro Mini has the ATmega328 running at 8MHz. I don't know the limitations and differences between the two. The believe the function is reading in 10 pulses with pulseIn() to recognize the IR.

Some direction would be great because I'm running out of ideas. If the TSOP2138 won't work with 3.3v without any issues... does anyone have any recommendations? I'm most likely going with a 3.3v system because many of the other components for the project run at 3.3v.

HELP! Thanks in advanced.

2

Bump :wink:

3

The receiver won't work with 3.3v. According to the datasheet it should be fine but I'm probably missing something.

Page 2 of the data sheet says minimum operating voltage (supply voltage) is 4.5V so I am not sure why you think it will work on 3v3.

It needs 5V, then it produces a 5V logic output, this needs a voltage conversion with a potential divider and catcher diode. Alternatively as you don't mind if the signal is upside down you could use a transistor to do the voltage conversion.

4

See... told you I missed something. I'm still pretty new to all this... got to learn somehow.

Would this be a better choice? http://media.digikey.com/pdf/Data%20Sheets/Sharp%20PDFs/GP1UE261X,267X,26X.pdf - Datasheet
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=425-1905-ND - Product

Thanks for the input.