gpio ir sender/receiver circuit or no?

[tony power]

Hi

I have raspberry pi 3 and 2.5A/5V power supply. there are gpio ir sender and ir receiver connected directly to pins
and they work very well both using LIRC software or controlling ir signals.
Each connected to 5v pins as shown in the image below.



original size
http://i.imgur.com/vA8QNuC.png

I am beginner in circuits, resistence and transisters.
I am not sure if this is safe and okay and not damaging rpi? I mean is it okay to output 5v from rpi to one ir sender and ir receiver without using a circuit with resistence or transistor.

[joan]

The sender will be fine as that is an output.

You need to measure the voltage at the GPIO used to receive the IR signal. It should be 3V3. If it is more you run the risk of damaging the Pi.

Could you post links to the IR modules you are using?

[tony power]

The sender will be fine as that is an output.

You need to measure the voltage at the GPIO used to receive the IR signal. It should be 3V3. If it is more you run the risk of damaging the Pi.

Could you post links to the IR modules you are using?

the link from aliexpress
http://m.aliexpress.com/item/32368989420.html

so is that fine? I don't need a transistor?

spec from link

IR is widely used in remote control. With this IR transmitter, the Arduin project is able to transmit command to any IR remote Receiver if you have the right decoder.
Well, it will be also easy to make your own IR controller using IR Receiver
Basedon the 38KHz IR Transmitter Sensor
Can be used for remote control
Power Supply : 5V
Interface : Digital
Modulate Frequency : 38Khz
Pin Definitions : (1) Output (2) Vcc (3) GND
Can be compatible with Wrobot Digital 38KHz IR Receiver Sensor
Apply to a variety of platforms including Arduin/51/AVR/ARM
Cable length: Approx.20c

[joan]

You need to measure the voltage at the output of the IR receiver. Arduinos mostly have GPIO which can handle 5V. The Pi doesn't.

[Massi]

you have to check the output of the receiver.
If it's an open collector output, it's ok (this means that it can work only if you pull up the line to 3,3V)
if it is not, you are inputting 5V and you are going to fry your pi

[tony power]

You need to measure the voltage at the output of the IR receiver. Arduinos mostly have GPIO which can handle 5V. The Pi doesn't.

you have to check the output of the receiver.
If it's an open collector output, it's ok (this means that it can work only if you pull up the line to 3,3V)
if it is not, you are inputting 5V and you are going to fry your pi

How can I measure the voltage?

I tested IR sender with 5v and IR receiver with 3.3v.

and IR receiver is still working.

How can I turn off IR receiver?
I recorded IR codes and I don't need it for now.
I want to turn it off but keep it connected to pins?

I am activiating ping using /boot/config.txt

using dtoverlay
and parameters for gpio input and output