HVLED805TR

STMicroelectronics Off-line LED Driver with Primary-Sensing

STMicroelectronics Off-line LED Driver with Primary-Sensing is a high-voltage primary switcher intended for operating directly from the rectified mains with minimum external parts to provide an efficient, compact, and cost effective solution for LED driving. STMicroelectronics Off-line LED Driver with Primary-Sensing combines a high-performance low-voltage PWM controller chip and an 800V, avalanche-rugged power MOSFET in the same package. The PWM is a current-mode controller IC specifically designed for ZVS (zero voltage switching) fly-back LED drivers, with constant output current (CC) regulation using primary-sensing feedback. This eliminates the need for the opto-coupler, the secondary voltage reference, as well as the current sense on the secondary side, while still maintaining a good LED current accuracy. Moreover it guarantees a safe operation when a short circuit of one or more LEDs occurs. In addition, the device can also provide a constant output voltage regulation (CV), which makes the application able to work safely when the LED string opens due to a failure. Quasi-resonant operation is achieved by means of a transformer demagnetization sensing input that triggers the MOSFET's turn-on. This input also serves as both output voltage monitor to perform CV regulation, and input voltage monitor to achieve mains-independent CC regulation.

HVLED805 Off-Line LED Drivers

STMicroelectronics HVLED805 Off-Line LED Drivers provide an efficient, compact, cost-effective solution for LED driving. The HVLED805 are high-voltage primary switchers for operating directly from the rectified mains with minimum external parts. STMicroelectronics HVLED805 Off-Line LED Drivers combine a high-performance, low-voltage PWM controller chip and an 800V, avalanche-rugged power MOSFET in the same package. The PWM is a current-mode controller IC specifically designed for ZVS (zero voltage switching) fly-back LED drivers, with constant output current (CC) regulation using primarysensing feedback.This eliminates the need for the opto-coupler, the secondary voltage reference, and the current sense on the secondary side while still maintaining a good LED current accuracy. Moreover it guarantees safe operation when a short circuit of one or more LEDs occurs.

IS32LT3175N/P Single-Channel Linear LED Drivers

ISSI IS32LT3175N/P Single-Channel Linear LED Drivers come with fade in/out and PWM dimming. The regulators serve as a stand-alone LED driver-configurable from 20mA to 150mA with external resistors, no microcontroller is necessary. A logic level “courtesy light” signal from the PWM pin can be interfaced to precisely drive the LED channel. The IS32LT3175P obtains a positive polarity PWM signal. In addition, the IS32LT3175N obtains a negative polarity PWM signal. The regulator integrates a 63-step fade-in and fades out the algorithm (Gamma correction). This causes the output LED current to increasingly rise up to the full source value after the EN pin is pulsed.