Designs (242)
The NCP3065 is a monolithic switching regulator designed to deliver constant current for powering high brightness LEDs. The device has a very low feedback voltage of 235 mV (nominal) which is used to regulate the average current of the LED string. In addition, the NCP3065 has a wide input voltage up to 40 V to allow it to operate from 12 Vac or 12 Vdc supplies commonly used for lighting applicati…
The Texas Instruments TPS61150EVM-150 evaluation module contains the TPS61150 IC. This EVM provides two independently regulated current outputs using a single inductor step-up (boost) converter.
This wide range evaluation board showcases the LM3424 NFET controller used with a buck-boost current regulator. It is designed to drive 4 to 10 LEDs at a maximum average LED current of 1A from a DC input voltage of 10 to 70V.
This design was developed to minimize the current spikes coming out of an electronic transformer to less than 5A, which is a typical transformer rating, when driving an LED MR16 circuit. The off the shelf LED MR16 solutions exhibit spikes that significantly exceed a transformers maximum rated output current which will degrade the reliability of the transformer and reduce its operating lifetime. T…
The LM3450A evaluation board is designed to provide an AC to LED solution for a 30 W LED load. Specifically, it takes an AC mains input and converts it to a constant current output of 700 mA for a series string of 1 to 13 LEDs (maximum LED stack voltage of 45 V). There are two assembly versions designed to operate from two different nominal AC input voltages, 120 VAC or 230 VAC.
* The eval board must be modified for 350mA output. The Transformer/Dual inductor and sense resistor(s). This circuit is intended for driving high power LEDs, such as the Cree XLAMP™ series, Lumileds Luxeon™ Rebel and K2 and OSRAM, Golden and Platinum Dragon™ as well as the OSTAR™.
This evaluation board is designed around an L6902D-based DC-DC converter with dimming interface. The board implements both of two well known dimming methods: - Analog current control - Average current control by PWM
* For Constant Current, the board must be modified as described on page 8 of the user guide. * Streetlight applications require that the power supply designed to power an LED lamp must have high efficiency and at least an equivalent lifetime in order to guarantee maintenance-free operation during the life of the LED.
Whenever a lighting application, such as street lighting for example, requires an elevated number of LEDs, there are basically two solutions: the first is to connect all the diodes in series in a single "string"; the second is to place several strings in parallel with fewer elements in each one.
The LM3404HV circuit and BOM have been designed to provide a constant forward current of 1.0A to a single LED with a forward voltage of approximately 3.7V from an input of 48V ±10%. Over the input voltage range of 6V to 75V the average LED current, IF, is 1.0A ±10%, the ripple current, ΔiF, will not exceed 400 mAP-P, and the switching frequency is 200 kHz ± 10%.