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1k 1/4w resistor is ok as coolwin suggested.

xia23 2019-05-16 09:59:36 ( reads)

Use  a 1/4 w, 1k ohm resistor should be ok as coolwin suggested.

The 1k resistor has Brown Black Red Gold (+/-5% or Silver +/-10%) for the color code. 

I measured a regular LED (2V , 20 mA, 5 mm in diameter, red LED, datasheet https://www.alliedelec.com/m/d/6355b8aba0b01578df0bb7b871ceefd7.pdf) with  a 12.4 V (constant Voltage) and 5A (constant cuttent) power supply, with this 1k resistor, the voltage drop on the red LED is 1.75 V, the current through the red LED is 8 mA.

5 mm LED of other colors (green, yellow etc.) should also be fine with this 1k resistor.

I haven't tried the flat LED, the 3rd on your picture yet. 20 mA 1.8-3.4 V (http://www.iled.com/class/INNOVAEditor/assets/YeniDatasheets/2715-2711(5mmkesikbas).pdf). But it should also be fine with 1 k resistor.

I don't have the first flat LED on your picture. There are some flat LEDs they use 5 V, 50 mA.

You used 360 ohm, 300 ohm and 300 ohm on the 1st, 2nd and 3rd LEDs (from the top down) on your picture (I assume the first color is Orange, not Red) is too small.

跟帖(5)

别在窗前等我

2019-05-16 14:53:36

got it~ thanks

xia23

2019-05-17 04:01:49

where did you buy the yellow and white translucent LEDs?

别在窗前等我

2019-05-17 08:23:43

from ebay

xia23

2019-05-17 16:01:08

kind of datasheets of 1W-100W High Power LED Chip COB Lights

xia23

2019-05-20 04:19:10

Read my 悄悄话 please, use a 7812 voltage regulator on your LEDs.