Irda Module project

If like me, you can't buy an IrDA module for your mother board, here you can find a simple circuit to build your own, hand made module.


Electronic Circuit
Click on the schematic to zoom in!!!! Now it can reach distances up to 35-40 cm!!! (wow!!!) :-)

Bill of material

Component Value
R1 1K Ohm 1/4W
R2 100 Ohm 1/4W
R3 220 Ohm 1/4W
R4 10K Ohm 1/4W
R5 10K Ohm 1/4W
R6 220 Ohm 1/4W
R7 10K Ohm 1/4W
R8 10K Ohm 1/4W
R9 470 Ohm 1/4W
R10 (optional) 19K Ohm 1/4W
D1 OP131 (or compatible IR LED)
D2 Green LED(used to monitor transmission)
D3 Green LED (used to monitor reception)
T1 2N2222 (NPN)
T2 2N2222 (NPN)
T3 OP845 (or compatible phototransistor NPN
T4 2N2222 (NPN)
T5 2N2222 (NPN)
T6 2N2222 (NPN)
IC1 74LS14

NB: The Base of T3 must be leaved disconnected to increase the gain)

Prototipe photos

Front Back
Here is 2 poor images of my prototype


If you want the original schematic, created with Arianna Draft, you can download ib by clicking HERE (59 downloads).


The circuit I developed, must be connected to the connector present on Pentium™ Mainbord TX and later.

Since the connector's pinout may change, you have to looking for correct pinout by reading your Mainboard user manual.

If your circuit can transmit, but doesn't receive, put a resistor of 10K Ohm between Vcc and RX. Some Mainboard do not have an internal pull up resistor.

If you want to use this circuit with Nokia Data Suite or another communication softwares, make sure you configured your IrDA port in Full Duplex mode.
Some BIOSes use other configuration options, like SIR or other.
Pay attention to choose the SIR mode (if available).

NB: I take no responsability for damages my circuit may cause.

PS: After IrDA upgrade, my PC works as usually, or better :-), but I risked damaging my friend's PC with a not well insulated circuit

2011/08/26 07:46

QR Code
QR Code hardware:irda_module (generated for current page)