Trying to convert an IR Torch

[johnbergman]

So I am trying to make an IR blaster/remote for my TV using an IR "Torch" I am having one problem, and that is finding out where to connect the data pin on the circuit shown. Any help would be appreciated.

 

[rjenkinsgb]

This is [hopefully] the datasheet for the controller IC on that board:

https://www.dianyuan.com/upload/community/2015/03/27/1427442373-56499.pdf

If that's correct, the EN pin, Enable / on/off control, is probably the top left one that's presently linked to the lower end of the big "151" resistor.

However, as the whole drive circuit uses a switched-mode system, the LED is already getting high frequency current pulses rather than continuous power - it may not be possible to modulate it at the required speed (around 40KHz) without the the SMPSU frequency interfering with that.

 

[schmitt trigger]

Not only that but the output PSU filter will completely attenuate the IR carrier.

 

[Nigel Goodwin]

What exactly are you trying to do?, and why?.

 

[johnbergman]

What exactly are you trying to do?, and why?.

Long range IR remote for our winter camp

 

[Tony Stewart]

How much time and money do you want to spend on re-inventing the $50 wheel?

Amazon.com

If you already knew the carrier frequency of your remote, you could simplify a design for that channel instead of a universal carrier. Sharp/Vishay devices are low cost and just need a simple linear regulator for detecting your remote. Then IR LED's and constant current modulated with data and carrier clock would be easy to drive with a string of fixed IR narrow beamwidth LED's running in pulsed burst carrier mode to resemble your torch using up to 100 mA current limited pulses with say <=10 deg degree LED's.


Rx https://www.vishay.com/en/ir-receiver-modules/

Suggested LEDs https://www.vishay.com/docs/81009/tsal6100.pdf 10deg 5mm $1 /string

Tx needs a CMOS Astable clock AND / NOR /NAND Data something like a 38 kHz clock carrier then CC current limiter with 2 transistors. I modified mine to reduce the Vbe drop with NFB.

All of this will easily work on a "perf" board. with a good 5V supply. Each of the resistors affects the current limit. There are other methods too.

SIMULATION https://tinyurl.com/yo4wfako

Make sure the Vishay Rx Vcc has low noise across IC with RC filter if necessary.

 

[Nigel Goodwin]

Long range IR remote for our winter camp

How long, and to do what? - a normal TV remote will easily reach in excess of 10m.

 

[schmitt trigger]

In addition to what Tony mentioned, you have to match both the IR transmitter and receiver’s wavelength.
There are two mainstream IR LED wavelengths, 850 and 940 nm. From what I have seen, most —although not all— IR receivers utilize 940 nm, therefore your best bet is to use this wavelength.

If the transmitter/receiver wavelength are not matched, the device will still work but with reduced sensitivity.