A digital AC/DC LED driver platform for commercial and wireless solid state lighting (SSL) systems has been unveiled by iWatt Inc. The first device in this new platform,is the iW3630 a two-stage, Flickerless LED driver with output power up to 45W and is believed to be the first SSL LED driver with a built-in 0V to 10V dimming interface for commercial lighting ballasts. It also supports a PWM digital dimming interface for wireless SSL applications.
The company advises the highly integrated design enables considerable savings in bill of materials cost compared in 0V to 10V applications and maintains a high power factor (PF) even at loads down to 20 percent of full load. It also offers a low total harmonic distortion (THD) of < 15 percent, to meet stringent global energy regulations, along with a built-in over-temperature protection (OTP) and derating function to improve the predictability and reliability of system operating life.
The device features a built-in isolation transformer driver works directly with 0V to 10V dimming systems, eliminating the need for additional driver circuitry components and costly microcontrollers, while the PWM digital interface simplifies integration into wireless lighting systems.
For commercial and wireless applications, the built-in over-temperature protection and derating function replaces the need for additional components to control heat. Also, the company’s PrimAccurate primary-side control technology replaces the need for a secondary-side regulator and optical feedback isolator, while EZ-EMI technology from the company simplifies EMI filtering, further minimising the external component count.
The digital control architecture of this device is said to simplifiy ballast driver designs by allowing it to adapt to wide input and output conditions. This enables one configuration to support a wide range of LED string lengths to cover the full output power range.
The companys Flickerless technology has been integrated into this device to eliminate flicker across the entire dimming range, while providing tight, ±5 percent LED current regulation. The company’s Flickerless technology incorporates a power factor correction (PFC) circuit comprised of a chopping circuit. This circuit ensures high power factor and also virtually eliminates the input line-voltage frequency component.
On-chip over-temperature protection and derating monitors the temperature inside the ballast. When thermal conditions reach a point set by the system designer, the LED driver automatically reduces the current drive to the LEDs, lowering the power dissipation and resulting in cooler overall operation. This avoids the risk of thermal runaway, ensures the temperature rating of the electrolytic capacitors in the lighting system is not exceeded, and allows a predictable operating life. Additional built-in protection features include LED open/short, input over-voltage, over-current, and current-sense resistor short protection.
iWatt
