Driving a mosfet pnp with an IR receiver.

Thread Starter

jriofrio

Joined Dec 8, 2014
93
That IC is basically an analog switch with digital control. That wouldn't work because it would require a latching circuit.
Are you still trying to find a non mcu solution?
Well not the MCU you mentioned.... I was just curious about it.
I going to use the attiny85, because I already have a programmer and most of all, there are many videos that explain its use.
The IR receiver switch that I have been talking in the forum, the one combined with the touch sensor, it has been working ok, but not a hundred percent. Sometime when I left the lamp on for long periods of time (like 2,3 hours), when I tried to turn it off, it goes off but almost immediately turns on by itself. I have to repeatedly, like 6 times in a row quick click with the remote, then turns off and stays off. Normally it turns on and off without any problem if the lamp don't stay on for long.
I connected a 100 ohm resistor between the output pin of the touch sensor and the mosfet gate, but it has make much of a difference. If you have any thoughts in what it could be the reason, I would like to hear it or any suggestions that I could look into..... Good day
 

sghioto

Joined Dec 31, 2017
8,737
I think if the output from IR sensor is filtered it would be reliable using in conjunction with the touch sensor.
I do have a design using a 555 if interested.
 

Thread Starter

jriofrio

Joined Dec 8, 2014
93
I think if the output from IR sensor is filtered it would be reliable using in conjunction with the touch sensor.
I do have a design using a 555 if interested.
Alright, how can I filter the IR receiver output? Could you draw a sketch please!
Didn't we already try the circuit with the 555?.... Or is it a new one?
 

BobTPH

Joined Jun 5, 2013
11,613
when I tried to turn it off, it goes off but almost immediately turns on by itself. I have to repeatedly, like 6 times in a row quick click with the remote, then turns off and stays off.
This is because, as I have told you before, the IR detector switches many times per button press and you still don’t have a circuit that handles that reliably.
 

Thread Starter

jriofrio

Joined Dec 8, 2014
93
This is because, as I have told you before, the IR detector switches many times per button press and you still don’t have a circuit that handles that reliably.
Ok, but only happens when the lamp stays on for more than 2 hours, otherwise it works fine.
 

Thread Starter

jriofrio

Joined Dec 8, 2014
93
Ok, but only happens when the lamp stays on for more than 2 hours, otherwise it works fine.
Well, I think I got the issue with the IR receiver switch problem solved.
Cause I have been looking for answer's of the erratic behavior of the IR switch, I went back to see all the info that I collected about the use of the IR receiver as a switch, and noticed a few people put a small capacitor between the negative and output pins of the IR receiver. The value and recommendations varies. So I soldered a 47uF and tested, the switching worked perfectly, but it took various seconds of waiting before I could switch on, the switch off was immediately but the switch back on needed to wait, so I changed the value of the electrolytic cap to 3.3uF and so far it has been behaving pretty well, it respond to the switching right away even after waiting for a couple hours. So, I guess something so simple enough to correct an erratic behavior.
 

sghioto

Joined Dec 31, 2017
8,737
I got one of those touch sensor modules to test with a TSOP3823 IR sensor I have on hand.
My results were not as reliable until adding a buffer transistor to the output of the sensor.

1688476548586.png
 

Thread Starter

jriofrio

Joined Dec 8, 2014
93
I got one of those touch sensor modules to test with a TSOP3823 IR sensor I have on hand.
My results were not as reliable until adding a buffer transistor to the output of the sensor.

View attachment 297659
Great, it looks promising. I'm egger to try.
It sure looks that it will be the solution to IR switching issue.... Thank you very much, I am really pleased.
I have been using the VS1838 IR receiver, I'm sure there is not much difference with the one you're using.
Best regards
 

Thread Starter

jriofrio

Joined Dec 8, 2014
93
It probably has to do with temperature then. The circuits @sghioto has been proposing would work consistently, too bad you haven’t tried them.
I will, it sure looks like more stable than mine.
Great, it looks promising. I'm egger to try.
It sure looks that it will be the solution to IR switching issue.... Thank you very much, I am really pleased.
I have been using the VS1838 IR receiver, I'm sure there is not much difference with the one you're using.
Best regards
Hello, good morning... Happy 4th of July.
Yesterday late night I put together your design. Problem, when I used the remote, the lamp switch on, but it turns itself off after 4 or 5 seconds. If I used the touch sensor, it works as expected. Don't know what it is going on.... I check and recheck the connection's, all is as in the sketch.
 

sghioto

Joined Dec 31, 2017
8,737
Could be a slight difference in the IR sensors. I tested the circuit over a 24 hour period without any issues.
Sure that transistor is a 2N3906?
 

Thread Starter

jriofrio

Joined Dec 8, 2014
93
Could be a slight difference in the IR sensors. I tested the circuit over a 24 hour period without any issues.
Sure that transistor is a 2N3906?
Yes, the transistor is the correct one. I check the specs of the IR receiver you mentioned in the sketch, it works at 30Khz and the one I am using works at 38Khz. I thought that won't make a difference, but I could be wrong... You know sometimes that happens
Anything it can be done to fix it?
 

Thread Starter

jriofrio

Joined Dec 8, 2014
93
Can I see the breadboard and the wiring?
Sorry, I was very confident that will work, so I incorporated in the lamp directly...
I can probably take pictures of the device itself, but because of the size and the way it's put together, it will make harder to make sense of it.... But I can try if it's ok with you.
 
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