# Infrared Receiver - Simple questions regarding data sheet and basic electronics

I've purchased a 36 kHz IR receiver (TSOP38436) but I'm still learning about electronics and I'm not sure how to connect this to my micro controller (Arduino). (Also, I'm using 36 kHz instead of the standard 38 kHz for my project because it requires 36 kHz)

1) The data sheet shows a Supply Voltage of 2.5 V - 5.5 V. Do I need to limit the current? The data sheet also shows a Max Supply Current of 3 mA, and a typical supply current of 0.35 mA (at 3.3v).

Does this mean I should use something like a 3.3k ohm resistor with 3.3v to supply around 1 mA to the receiver?

2) The Application Circuit shows a resistor and circuit (R1 and C1) but I think they are only recommended for supply voltages less than 2.8v.

How would I know what values to use here?

3) Stupid question, but if I directly connect the receiver to an Arduino 3.3v with no resistor, then will that short circuit and blow the resistor sending too much current?

1) NO 3mA is all that it uses max.
2) NO. Because it is to reduce ripple which reduces the internal signal/noise ratio (SNR) from supply noise. This is just a low pass filter. Perhaps choose R1 for <0.3V drop max @ 3mA or <100 Ohms and C to attenuate expected ripple f for mV(pp). The TSOP384xxx series has better AGC for CFL stray light pulses. The effect of supply ripple is to reduce range at the threshold of errors. We do not know your system ripple f and value in Vpp. Ideally it uses another clean LDO for max range ( 30m est.)
3) NO but, Short to ground only draws 3V/30k= 100 uA.
But a short to 3V based on VOSL=100mV/IOSL = 0.5 mA = 200 Ohms, will draw more than 15mA.

Use the application circuit diagram to connect to the Arduino. Since you are using 3.3V, you don't need R1 and C1 (short instead of R1, simply omit C1). The "Output" pin should be connected to a GPIO of the Arduino.

The "Max Supply Current" is the maximum current that the part will draw, not what you need to limit it to. You rarely have to limit the current to a module.

1) No. That specification means you need to give it 2.5V - 5.5V, and it will draw no more than 3mA. Putting a series resistor in there (beyond their suggested RC network) will only screw things up.

2) Correct. You can probably leave it off. Don't worry about it -- just connect Vs to +5V or +3.3V, whichever you're using.

3) No.