Fluorescent ballast topology usually includes line conditioning for CE and UL compliance, a power factor correction block including a boost converter to 400 V for universal input applications and a half bridge inverter.

The ambient light adaptive LED driver automatically adjusts display brightness for changing ambient light conditions, providing a more viewable display with better contrast. The design drives five series connected LEDs from an input voltage of 4.5V to 12V. The LED current is nominally 100mA and the output voltage is 15 to 20V.

Demonstration circuit DC1666A is a synchronous four switch buck-boost LED driver controller. It accepts an input voltage from 4.7V to 60V, and drives up to 25V of LEDs at 2A. DC1666A features both PWM and analog dimming of the LED string. It has an OPENLED flag that indicates when the LED string has been removed and it has a SHORTLED flag that indicates that the output has been shorted to GND. In…

Demonstration circuit 1224 is a LED Driver with One Wire Control and Output Disconnect featuring the LT3593. The LT3593 is a step-up current mode DC/DC converter designed to drive up to 10 white LEDs in series from a Li-Ion cell. The demo board has two sections. The top section showcases the small size LED drive. The maximum current is 20mA. The bottom section is the control section that generate…

Demonstration circuit 843 is a high current boost LED driver featuring the LT®3479 and the AOT 3218 Flash LED. The board is optimized for 700mA 300ms LED flash current or 150mA constant LED torch current with a single lithium ion battery input voltage range of 2.7V to 4.5V.

DC484A features the LT1937 constantcurrent white LED driver in a small SOT23 ThinSOT package. The demo board is designed to demonstrate the high efficiency performance and the small size of the LT1937.

Demonstration circuit 994 features the LT3003 three channel LED ballaster with PWM in a 10-lead MSOP thermally enhanced MSE package. The demonstration circuit is designed to ballast three channels of LED current from 100mA to 350mA per channel. The PWM dimming function of the LT3003 eliminates the need for discrete MOSFETs. The LT3003 internally performs the level-shift required for non-ground re…

Demonstration circuit 773 is a synchronous buck-boost 1MHz Luxeon III white LED driver featuring the LTC3441 and LTC2050. The board is optimized for 3.9V LED forward voltage output at 1000mA load current and a single lithium-ion input voltage range of 3V to 4.2V. With its high frequency, synchronous buck-boost internal power switches, low quiescent current, 1MHz switching frequency and thermally …

This document describes the proposed solution for a universal-input 2.4W LED ballast using the FL7701. The input voltage range is 90VRMS – 265VRMS and there is one DC output with a constant current of 85mA at 28VMAX.

Demonstration circuit 1470A is a high current synchronous step-down LED driver with three-state control featuring the LT®3743EUFD. The demo board is optimized for 20A output from a 12V input. Being an LED driver, the output current is being regulated until the output voltage reaches a programmed voltage limit. This voltage limit on this demo board is set to around 6V by R5 and R6. The 6V is chose…