LM3552 white LED driver
A simple led driver electronic project can be designed using the LM3552 white LED flash driver integrated circuit .
For this led driver electronic project you will need a DC power supply circuit that provide an output voltage between 2.7V and 5.5 volts ( supply voltage must be applied between Vin and GND .
EN jumper connects the “OFF” post to the middle post of the EN header strip. This connects GND to the EN pin of the LM3552, disabling the part.
The T/F jumper connects the “T” post to the middle post of the T/F header strip. This connects GND to the T/F pin of the LM3552, placing the part into the 200mA torch mode when the part is enabled .
When these connections are all made correctly, the Flash LED will be OFF. Setting the EN jumper to the ON position will enable the part and turn on the flash LED. In torch mode, the LED current will be set to approximately 200mA. Placing the T/F jumper across the ’+’ pin and the T/F pin enables flash mode. The total current delivered to the LED is approximately 700mA. If this jumper is left in flash mode, the internal time-out circuit will disable the switcher after approximately 1 second.
The EN pin has an internal pull-down resistor placing the part in shutdown by default and the T/F pin does not have a pull-up or pull-down resistor. If left unconnected, it is unknown as to whether the LM3552 is in torch or flash mode.
As you can see in the circuit diagram , these design is very simple and not require many additional components .