• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

3.7 volts LED with 2 volts

Status
Not open for further replies.

Grimchuck

New Member
Hello, first i want to say that my knowledge in electronique is very basic.

I have a old NES (nintendo) 8 bits and i want to replace the red LED by a blue LED. Someone check the voltage output for the LED on my NES and told me that it was 1.97 volts. The probleme is that all the blue i can find are 3.7 volts, so i dosent llight on with 2 volts. Does 2 volts bright blue LED exist? and if not, is there a way to light on a 3.7 v LED with 2V?

Ifound that on internet http://nr.stic.gov.tw/ejournal/KB/kb9110_e.pdf

Could something like can help me?

Thanks
 

Josh

New Member
Have you actually removed the red LED and tried the blue LED in it's place? because it should still work - 3.7V would probably be it's recommended power.
 

Grimchuck

New Member
No i did not removed the red LED. i plugged the blue LED in parralel with the red and did not light on. In in a electronic shop near my place they told me it was because the LED i must use is 1,85 volts and Blue LED with that voltage dosent exist. They also told me that 3,7 volts LED will not light on with an output of 1.97volts.
 

Sebi

Active Member
Try with removed red LED. I the circuit supply is 5V it will work. If the luminance not enough, decrease the serial resistor, but the supply is only 3V, no chance.
 

Sebi

Active Member
From what battery coming 1.9V? I think You've measured this voltage on red LED. The circuit supply must be 3 or 5V. Have You changed the LED and so measured?
 

Sebi

Active Member
O.K. On this panel You can't measure the supply voltage, only the LED voltage. Try change the LED, no risk.
 

bogdanfirst

New Member
it is very likely that the led has a series resistor in series with it. look at the wire coming from the led and going to the other board. what it is connected to. follow the copper wire line and you might go to a resistor.
you need to put a smaller value resistor in place of that, or another resistor in paralel with it.
but first remove the red led and put the blue led in place.see if it works
 
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading
Top