Need help with 3 specific resistor values... (1.37K, 3.94K, & 150 Ohms)

Ok so I need three very specific resistor values, (less than 5% tol) the reason the resistor values have suuch a small tollerance is because i'm useing them to control the brighness of the 3 LEDs in a RGB LED, if the values vary even slightly the white light will have a notacible discoloration.

So what i need help with is setting up the following resistors in some configureation...
Note: I have 100 resistors of each and I only need to have 4 configurations of each value & I prefere somthing simple to 50% complex
also I cannot use pots nor can I buy new resistors unless someone has somespares that they can mail me & yes it's probable I can pay postage

• 100
• 150
• 510
• 180
• 470

I also have 10 of each of the following

• 1k
• 10k
• 100k

thanks for the help!

5% is not a small tolerance, by a long shot.
Exactly why can't you use pots?

1kΩ + 180Ω + 180Ω = 1.36kΩ (10Ω short)
1kΩ + 1kΩ + 1kΩ + 470Ω + 470Ω = 3.94k
150Ω = 150Ω

DemonicSandwich said:

5% is not a small tolerance, by a long shot.
Exactly why can't you use pots?

1kΩ + 180Ω + 180Ω = 1.36kΩ (10Ω short)
1kΩ + 1kΩ + 1kΩ + 470Ω + 470Ω = 3.94k
150Ω = 150Ω

Click to expand...

ok ty thats all i need

Here is a resistor combination & ratio spread sheet that I produced some time ago.

You can make up a wide range of values using only 2 resistors, either in series or in parallel.

For 1.37 k, the nearest is 1.5 k // 15 k = 1.364 k

For 3.94 k, the nearest is 0.047 k + 3.9 k = 3.947 k

// = in parallel

FWIW: Electronic Components Distributor | DigiKey Corp. | US Home Page sells resistors in packs of 5, not 100.

KeepItSimpleStupid said:

FWIW: Electronic Components Distributor | DigiKey Corp. | US Home Page sells resistors in packs of 5, not 100.

Click to expand...

Most all distributors sell them in quantities of less than 100.

Digikey may have a larger selection of components than basically all others suppliers, but they also charge a 25%-50% markup on many of those products.