# LED driver found by the sidewalk...

#### Externet

Joined Nov 29, 2005
2,087

Has a coaxial power jack and marked

Output:
Constant current : DC350mA 0.5V...7.2V
Constant voltage: DC 8.5V | <300mA

How is that supposed to be used;
for any LED strip meant for less than 7.2VDC and exactly 350ma current ?
If the consumption of the load takes less than 300mA, then this thingy outputs a fixed 8.5V ?

#### Dodgydave

Joined Jun 22, 2012
10,939
It will give out constant current at 350mA, as the load varies in resistance it will maintain the current within the voltage range of 0.5 to 7.2V..

#### MikeML

Joined Oct 2, 2009
5,444

Has a coaxial power jack and marked

Output:
Constant current : DC350mA 0.5V...7.2V
Constant voltage: DC 8.5V | <300mA

How is that supposed to be used;
for any LED strip meant for less than 7.2VDC and exactly 350ma current ?
Yes.
If the consumption of the load takes less than 300mA, then this thingy outputs a fixed 8.5V ?
Yes.

Another way of saying it: It is a voltage-limited (to 8.5V) constant-current source of 350mA.

#### spinnaker

Joined Oct 29, 2009
7,830
Current for an LED needs to be limited. When you do not care about power consumption, a resistor input in series with the LED. Cheaper and easier to build.

The device you found is switching constant current supply so it is very efficient.

The first spec says the LEDs need to operate between .5V and 7.V and then the current will be limited to 350ma.

The second spec is very odd. Not sure what the heck it means.

#### spinnaker

Joined Oct 29, 2009
7,830
If the consumption of the load takes less than 300mA, then this thingy outputs a fixed 8.5V ?
Thinking about it again I think you are right. It is saying that if the circuit only requires <300 ma the output will be 8.5V.