STEVAL-ILL008V1

STEVAL-ILL008V1 is a LED flashlight evaluation board based on the L6920DA converter. White LEDs are gaining popularity as sources of illumination due to their high efficiency and reliability. Typical forward voltage drop across a white LED is approximately 3.5V. When these LEDs are powered from a single or two cell batteries, a boost converter is needed to boost the voltage to drive the LEDs. This board, based on the L6920DA, implements a high efficiency step up converter which requires very few passive components to perform the conversion from the battery voltage to the selected output voltage or current. Start up is guaranteed at 1V and the device operates down to 0.6V. The device has a very low quiescent current. An internal synchronous rectifier is implemented with a P channel MOSFET, replacing the conventional boost diode, to improve efficiency. This also could reduce the cost of the application since no external diode required.

• 0.8V start up input voltage
• Up to 5.5V operating input voltage
• Internal synchronous rectifier
• Adjustable output voltage from 1.8V
• 3.3V and 5V fixed output voltages
• Low battery voltage detection
• Reverse battery protection
• 750mA input current limit
• Switching frequency up to 1MHz
• 1.23V reference voltage available

Applications

Power Management, LED Lighting