I have an IR LED (IR383), and I want to power it with 5v@38KHz. I'm actually calculating the resistor so I need the LED's maximum current. In the datasheet, it says that it accepts 100mA continuous and 1A peak, this being at Pulse Width <= 100uS and 1% duty. How can I calculate, using this information, the peak maximum current with my 38KHz (50% duty)?

(1/38KHz = 26.3157895uS)

  • \$\begingroup\$ @delanymichael The thing is that, at 100mA, the light can't reach far enough. Also, I can't be sure that I will be able to power it at 1A with that statement because it says 100uS@1% duty and I need 26.3uS@50% duty. \$\endgroup\$
    – Iaka Noe
    Feb 23, 2018 at 3:06
  • \$\begingroup\$ So at what current does it reach far enough? \$\endgroup\$ Feb 23, 2018 at 3:07
  • \$\begingroup\$ @StainlessSteelRat didn't test because I don't know how high can the current be and I don't want to burn them. \$\endgroup\$
    – Iaka Noe
    Feb 23, 2018 at 3:08
  • \$\begingroup\$ You need to include a link to your IR LED. You need to include the distance you want to reach. And sadly, you are going to have to experiment. As in sacrifice IR LED's to the electron gods. \$\endgroup\$ Feb 23, 2018 at 3:17
  • \$\begingroup\$ @delanymichael Yes, I know. But my resources and physical space on the PCB won't allow me to put more than one LED. That's why I'm asking. BTW, Why are you being so aggressive? \$\endgroup\$
    – Iaka Noe
    Feb 23, 2018 at 3:28


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