LEDs and Dropping Resistors
 Share
The version of the browser you are using is no longer supported. Please upgrade to a supported browser.Dismiss

View only
 
 
ABCDEFGHIJKLMNOPQRS
1
2
3 white LEDs in series with 220 ohm 1/2 watt resistorVoltage AppliedCurrent through circuit in milliampsRelative Light OutputVoltage Drop over ResistorTotal Circuit Power Consumption in milliwattsPower consumed by the dropping resistor in milliwattsPercentage of total power wasted in dropping resistorRelative Light Output per Circuit WattLight Efficiency Relative to 12.5V Value
3
9.551361.0848511%286141%
4
10.071861.45701015%266130%
5
10.582111.75841417%251123%
6
11.0102622.181102220%238117%
7
11.5123032.541383022%220108%
8
12.0133392.871563724%217107%
9
12.5153823.291884926%204100%
10
13.0174203.682216328%19093%
11
13.5194564.082577830%17887%
12
14.0214904.482949432%16782%
13
14.5225204.8431910633%16380%
14
15.0245525.2736012635%15375%
15
15.5265805.6740314737%14471%
16
16.0286096.1144817138%13667%
17
18
19
Measured with:BK 1743 variable power supplyFluke 117 DMMExtech Lux MeterFluke 123 Scopemeter
20
21
22
23
24
25
Same test with 150 ohm resistorVoltage AppliedCurrent through circuit in milliampsRelative Light OutputVoltage Drop over ResistorTotal Circuit Power Consumption in milliwattsPower consumed by the dropping resistor in milliwattsPercentage of total power wasted in dropping resistor
26
9.570.93567710%
27
10.091.27901113%
28
10.5101.561051615%
29
11.0131.951432518%
30
11.5162.311843720%
31
12.0182.622164722%
32
12.52032506024%
33
13.0233.362997726%
34
13.5253.773389428%
35
14.0284.1239211529%
36
14.5314.5545014131%
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Loading...