chimo
Flashlight Enthusiast
Here is some test data for the ArcMania 50mA 10mm driver.
Current measuring was done with:
a 0.1 ohm (1%) resistor on Vin (Vin was measured at the board)
a 0.05 ohm (1%) resistor in line with a Nichia DS LED on the output
Turn on transition was around 0.77V.
I checked the slight dip at 1.5V twice to be sure.
Efficiency is not too bad for a 1.5V boost driver 60-70%.
Current regulation is not bad either between 1-1.7Volts in.
Note that this chart has two Y axis. (Power on the left and Efficiency / Output Current on the right)
Here is the same profile for the ArcAAA.
Same LED and sense resistors used.
Here is comparison of the two.
Observations:
I have graphed similar portions of the Vin range for each of these converters.
They both require around the same trigger voltage to turn on (~0.8V), however, the ArcAAA converter has a bootstrap configuration. Once it is running, it will continue run down to a Vin of <0.1V. The ArcMania MC will turn off between 0.7-0.8V.
So what? - you may ask? If you are running secondary batteries (NiMH) and want over-discharge protection for the cell, the ArcMania converter is a better option. If you are running primary cells (Alkaline/L92), the ArcAAA converter will drain the battery completely.
Effective battery voltage ranges (consider this when examining the graphs):
Alkaline: 0.8-1.5V
NiMH: 0.9-1.3V
L92 (Lithium): ~1.1-1.6V
Efficiency Comparison
Output (LED) Current Comparison.
Current measuring was done with:
a 0.1 ohm (1%) resistor on Vin (Vin was measured at the board)
a 0.05 ohm (1%) resistor in line with a Nichia DS LED on the output
Turn on transition was around 0.77V.
I checked the slight dip at 1.5V twice to be sure.
Efficiency is not too bad for a 1.5V boost driver 60-70%.
Current regulation is not bad either between 1-1.7Volts in.
Code:
Iin(mA) Vin(V) Pin(mW) Iout(mA) Vout(V) Pout(mW) Eff(%)
84.5 1.7 143.7 29.2 2.982 87.1 60.6
110.8 1.6 177.3 39.2 3.075 120.5 68.0
99.2 1.5 148.8 30.2 2.993 90.4 60.7
124.3 1.4 174.0 38.2 3.064 117.0 67.3
152.7 1.3 198.5 45.6 3.13 142.7 71.9
149.6 1.2 179.5 40.4 3.085 124.6 69.4
166.3 1.1 182.9 38.8 3.078 119.4 65.3
180.1 1 180.1 36 3.054 109.9 61.0
126.3 0.9 113.7 19 2.886 54.8 48.2
46.2 0.8 37.0 1.6 2.603 4.2 11.3Note that this chart has two Y axis. (Power on the left and Efficiency / Output Current on the right)
Here is the same profile for the ArcAAA.
Same LED and sense resistors used.
Code:
ArcAAA Converter
Vin(V) Iin(mA) Pin(mW) Vout(V) Iout(mA) Pout(mW) Efficiency (%)
1.7 252 428.4 3.385 81 274.2 64.0
1.6 251 401.6 3.296 72.2 238.0 59.3
1.5 252 378.0 3.251 66.2 215.2 56.9
1.4 256 358.4 3.205 59 189.1 52.8
1.3 259 336.7 3.148 51.6 162.4 48.2
1.2 211 253.2 3.089 43.8 135.3 53.4
1.1 158 173.8 3.015 34.8 104.9 60.4
1 120 120.0 2.933 25.2 73.9 61.6
0.9 104 93.6 2.886 20.2 58.3 62.3
0.8 90 72.0 2.832 15.4 43.6 60.6
0.7 75 52.5 2.779 11.4 31.7 60.3
0.6 60 36.0 2.727 8 21.8 60.6
0.5 49 24.5 2.683 5.2 14.0 56.9
0.4 37 14.8 2.637 3.4 9.0 60.6
0.3 27 8.1 2.596 1.8 4.7 57.7
0.2 17 3.4 2.55 0.8 2.0 60.0
0.1 8 0.8 2.475 0.2 0.5 61.9Here is comparison of the two.
Observations:
I have graphed similar portions of the Vin range for each of these converters.
They both require around the same trigger voltage to turn on (~0.8V), however, the ArcAAA converter has a bootstrap configuration. Once it is running, it will continue run down to a Vin of <0.1V. The ArcMania MC will turn off between 0.7-0.8V.
So what? - you may ask? If you are running secondary batteries (NiMH) and want over-discharge protection for the cell, the ArcMania converter is a better option. If you are running primary cells (Alkaline/L92), the ArcAAA converter will drain the battery completely.
Effective battery voltage ranges (consider this when examining the graphs):
Alkaline: 0.8-1.5V
NiMH: 0.9-1.3V
L92 (Lithium): ~1.1-1.6V
Efficiency Comparison
Output (LED) Current Comparison.
Last edited:
