I'm looking for some guidance choosing a new IR LED to give me significantly more IR output on my IR remote transmitter. I'm in a time crunch so I need to order all my parts to experiment with in one shot.
I've built this little Velleman IR remote transmitter (schematic below) and it functions, but doesn't put out nearly as much IR light as need, as this will be used outside in the daytime and needs to overcome natural IR light. I'm thinking my best option is more powerful LEDs to replace LD1 and LD2, does anyone have a suggested model?
I think LD1 and LD2 are the weak link because of the following; using my scope I can see the voltage drop across LD1 and LD2 is about 3v during a pulse (the anode of LD1 never dips below 3v during a pulse), and this more or less matches the datasheet. Measuring at the cathode of LD2 I can see that T1 is pulling down to about 0V so I believe T1 is fully turning on. So as best I can tell, LD1 and LD2 are at full capacity and just don't put out much light. I could also try replacing R3 with a smaller value, but I'm not sure what that's going to do to the life of these LEDs. All suggestions are welcome!
Data sheets:
LD1/LD2: https://www.rcscomponents.kiev.ua/datasheets/l-934f3bt.pdf
T1: http://www.micropik.com/PDF/bc635.pdf
I've built this little Velleman IR remote transmitter (schematic below) and it functions, but doesn't put out nearly as much IR light as need, as this will be used outside in the daytime and needs to overcome natural IR light. I'm thinking my best option is more powerful LEDs to replace LD1 and LD2, does anyone have a suggested model?
I think LD1 and LD2 are the weak link because of the following; using my scope I can see the voltage drop across LD1 and LD2 is about 3v during a pulse (the anode of LD1 never dips below 3v during a pulse), and this more or less matches the datasheet. Measuring at the cathode of LD2 I can see that T1 is pulling down to about 0V so I believe T1 is fully turning on. So as best I can tell, LD1 and LD2 are at full capacity and just don't put out much light. I could also try replacing R3 with a smaller value, but I'm not sure what that's going to do to the life of these LEDs. All suggestions are welcome!
Data sheets:
LD1/LD2: https://www.rcscomponents.kiev.ua/datasheets/l-934f3bt.pdf
T1: http://www.micropik.com/PDF/bc635.pdf