white LED cluster , would like to make it flash - constantly on.

[Fida]

--------------------------------------------------------------------------------

Hi i have White LED cluster and would like it to flash and also remain constantly on. Just as you may have seen on a bike light.

The only problem is i am using a 3.7v 650ma mobile phone battery, and would like the circuit diagram for the above mentioned.

The LED cluster is drawing 400ma. Please could anyone help me with the circuit diagram. I am trying to get high brightness out of the LED,s so the circuit must have at least 400ma output.

Can anyone help?

Thank you

fc

 

[Ubergeek63]

--------------------------------------------------------------------------------

Hi i have White LED cluster and would like it to flash and also remain constantly on. Just as you may have seen on a bike light.

The only problem is i am using a 3.7v 650ma mobile phone battery, and would like the circuit diagram for the above mentioned.

The LED cluster is drawing 400ma. Please could anyone help me with the circuit diagram. I am trying to get high brightness out of the LED,s so the circuit must have at least 400ma output.

Can anyone help?

Thank you

fc

White cluster on a tail light? you should be using a single lighting class red LED. Cluster LEDs have ridiculously low efficiency, a single lighting class LED will blow it away for half or less the power.

 

[HarveyH42]

650mA battery, 400 mA load... Doubt it will last even an hour. A 10 ohm 1/2 watt resistor in series should be okay to light it up continuously. Plenty of simple circuits to flash an led, the problem would be the 3.7 supply voltage, and switching 400 mA.

 

[k7elp60]

Another way to consider is to turn the LED's on for a short time at a fast rate. To the human eye they will appear to be on all the time yet they are not. The total current drain on the battery will be much less. One method is called charlieplexing.