Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

IR leds and forward voltage drop

Status
Not open for further replies.

izua

Member level 3
Joined
Oct 31, 2006
Messages
63
Helped
2
Reputation
4
Reaction score
0
Trophy points
1,286
Activity points
1,888
I'm designing my own remote, for a custom protocol. I know there are a few tricks with using IR leds to save battery, but I'm not really sure which. I know that they can be put in series to increase brightness, for example, but how exactly should this be done?

How do you 'check' them, when you work with IR projects, since you can't see them?

And also, is there an easy way to measure their fwd voltage drop?
 

Eumel

Member level 1
Joined
Dec 12, 2001
Messages
35
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,286
Activity points
244
At 5V you can put 2 or 3 LEDs in series.

Use a digital or video camera to see them work.

LED in series with 100 Ohm resistor. Increase the voltage of a variable power source until you reach the nominal current e.g. 20 mA. Measure the foreward voltage at the LED with a multimeter.
 

izua

Member level 3
Joined
Oct 31, 2006
Messages
63
Helped
2
Reputation
4
Reaction score
0
Trophy points
1,286
Activity points
1,888
would i need a series resistor with the leds seried up? i'm trying to make something really low power.
 

Joined
Sep 3, 2007
Messages
853
Helped
66
Reputation
132
Reaction score
16
Trophy points
1,298
Activity points
0
You can consult the led's datasheet, it surely contain the information you need.
 

izua

Member level 3
Joined
Oct 31, 2006
Messages
63
Helped
2
Reputation
4
Reaction score
0
Trophy points
1,286
Activity points
1,888
They're cheap bulk leds. No datasheet, that's why i'm asking :)
 

Status
Not open for further replies.
Toggle Sidebar

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top