Velleman VM120 - 10-Channel 12Vdc Light Effect Generator Mod

Modules General
1

I am proposing to run 5W COB lights from each channel of the VM120 Light Effect Generator Mod for a one off project, limiting the current to the specified 400mA, using resistors between the channel output and the COB. The 12v COB requires a forward voltage of about 9volts, which will be provided by a total series impedance/resistance of about 7.5 ohms, 1.2W at a controller current of 400mA. Can you advise the channel output impedance so I can determine what additional resistance is required? Alternatively can you advise the output voltage at no load and the output voltage full load (400mA) so that I can calculate the impedance?

One other thing, can you advise the minimum input voltage for the controller - I’m looking at battery specifications and at a battery rating of 8Ah the voltage drops to 10-11V at 4A discharge current? I presume the output voltage would be in proportion to this input voltage?

Thanks

2

Channel output impedance is (theoretically) 0 ohms, since there is no series resistor.
Output transistors are BC640.
According to the datasheet, the loss over the transistor can be 0.5V max. at 500mA
Outputs are connected to power supply input, there is no series diode, so voltage should be equal to input voltage.
Unit should work fine with battery voltage down to 10V.