DX Li Ion 5 Mode

[vetkaw63]

I have read that these boards drop excess current. Does that mean on low that they consume just as much current as on high? It is not going to the emitter, just being dropped?
Thanks,
Mike

 

[KrisP]

Nope, the input current drops with the mode selected. I tested a few of them for voltage change and measured input voltage, input current, output voltage and output current... When medium or low were selected the input and output current dropped to the same level (+ or - a few mA). The circuit seems to set a maximum current level for whatever mode it is on, but also has a voltage drop. On high mode with a 4.2v input, the output is around 3.75v and output current around 960mA, but by the time the battery drops to 4v the voltage drop across the circuit has caused the output to go down to 3.65v. Depending on your LED, at this voltage it might draw less current. My Seoul P4 V0 from Photonfanatic was only drawing 820mA from the circuit by the time the power supply was down to 4v.

Test results:
http://www.dealextreme.com/forums/Forums.dx/Forum.6190~threadid.18247

 

[vetkaw63]

KrisP,
Thanks for the response. Did you do any run times on all the levels?
Mike

 

[KrisP]

No runtimes, I only have a power supply at work and couldn't waste too much time not working

 

[TorchBoy]

Don't know about this "input current" and "output current" business since the LED is in series with the controller, and the "Supply Current Consumption" is just 200uA according to the datasheet. I suppose it's the easiest way to talk about the two values though.

Hey, you measured an average of over 20 times the spec supply current consumption. What does that mean? Darn nominal values?

 

[nanotech17]

are they comes pre soldered?

 

[TorchBoy]

are they comes pre soldered?

AFAIK the red and white wires are not soldered. Everything else should be.

 

[KrisP]

I think the current input vs the current output difference might have just been a difference in the meters. I had 4 different multimeters connected up to measure the voltages and currents.

 

[TorchBoy]

I had 4 different multimeters connected up to measure the voltages and currents.

Wow. That's quite a setup.