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IR receiver that works at 3.3v for Pi Pico

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(@sealyons62)
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Joined: 2 years ago
Posts: 4
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I'm looking for an IR receiver that works at 3.3v for use in Pi Pico projects. Most of what I can find d requires 5v. Does anyone have any suggestions?


   
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(@dronebot-workshop)
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Joined: 5 years ago
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The TSOP382 works from 2.5 to 5.5 volts.

😎

Bill

"Never trust a computer you can’t throw out a window." — Steve Wozniak


   
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THRandell
(@thrandell)
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Hi @sealyons62

What's your application?  The TSOP that Bill mentions is one of Vishay's remote control options, their TSSP line is better for proximity applications.  I'm currently using the TSSP94056 fast proximity receiver for a robot application.  Supply voltage is 2.0V to 3.6V and the carrier frequency is 56kHz

When I was just starting to play with remote control I used the TSOP38238 that Bill mentions.  That has a carrier frequency of 38kHz and works as well as the receiver on my TV set...

Tom

To err is human.
To really foul up, use a computer.


   
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(@sealyons62)
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Joined: 2 years ago
Posts: 4
Topic starter  

Just playing at the moment. Have ordered the TSOP to just experiment a bit using IR with the Pico. If I decide to do an actual project build using IR I may investigate other options. What are the main differences in performance between the TSOP and the TSSP that you're referencing?  Does operation at 56Khz give you a cleaner signal and less interference? What are the cost differences? Any other issues using that over the TSOP? Thanks for any help.

This post was modified 1 year ago by sealyons62

   
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THRandell
(@thrandell)
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Posted by: @sealyons62

What are the main differences in performance between the TSOP and the TSSP that you're referencing?  Does operation at 56Khz give you a cleaner signal and less interference? What are the cost differences? Any other issues using that over the TSOP?

Hmmm, my work with these receivers started with the Arduino and now I do everything on the Pico so it's hard for me to make meaningful comparisions between the TSOP and TSSP.  I do remember that with the TSOP a remote control worked over a wider range of angles when pointed at the receiver, the data sheet calls it directivity or angle of half transmission distance.  The TSOP was also a bit more consistent with the timings I was recording from the remote control.  That was all on the Arduino running a program I plagiarized from Adafruit.

The increased carrier frequency gives me more throughput.  Which is what I want from my application.  Interference and surface reflectivity are other topics that I haven't bothered measuring.  I'm using $2 USD receivers so my expectations are pretty low.

Costs are similar I think.  If you can find them I recommend the '94' series from Vishay.  It's their latest technology and the reason for the lower supply voltage.

Another thing I just thought of is that the TSSP comes in at least two flavors. The TSSP58038 has binary output and uses fixed gain while the TSSP58P38 has analog output (pulse width) and automatic gain control which allows it to measure distance!  The TSSP58P38 is slow though, like 5Hz.

<begin plug> I do want to give a plug for using these with the Raspberry Pi Pico.  Setting up PWM is straight forward and you can use interrupts to control the encoding and decoding of IR signals.  For my robot application I can sent a 32 bit 'message' using the PWM_IRQ_WRAP to fire the IR emitter on and off while at the same time recording the IR reflection using a GPIO interrupt connected to the TSSP output pin.  When the transmission ends I know immediately whether the robot received it's own message or that of another robot. <end plug>

 

Tom

To err is human.
To really foul up, use a computer.


   
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