The foreword LED manufacturer suggested that causes the sunlight emitter diode through the control forward current maintains the fixed luminous flux and the specific color temperature. In view for this fact that the LED brightness with is being proportional to the magnitude of current, this control method is the best LED power source package. In addition, the LED direct voltage and the output receives the junction temperature the strict limit, specially best quality LED is so;
The junction temperature could be the well known influence quality and the service life key parameter. Accurately speaking, elevates along with the junction temperature, the direct voltage and the output will reduce gradually, the drifting can cause the critical current to elevate. For through reduces the direct voltage to solve the hot drifting problem, enhances the equipment overall energy efficiency, adjusts the light technical control brightness through PWM or even simulation, obtains against expiration management and the overheat control function, the lighting system to has unique control function LED driver's demand to enhance tirelessly. If for applications and so on construction illumination and street lighting increases the value, but also needs to increase the remote control function in the LED driver. Because the high efficiency factor exchange - transformer can transform the electrical network alternating voltage Cheng Genggao the input DC voltage, therefore illuminates the LED driver usually to use the basic model voltage dropping analysis situs ordinary, this kind of driver based on integrates a power switch's simulation monolithic solution, the maximum output electric current achieves 350mA. If the voltage is higher than 50/60V, because of the chip technology limit, the monolithic solution will be unable to be competent.
Many illumination platforms need these to use many driver's multi-channel output systems, but this will increase the system construction and the domain design complexity, finally will cause the designed cost to increase. Several solution mainly with concerns using the limit as per the parallel resistor and the internal comparator's electric current examination method. The comparator carries on from the keen resistor back coupling's electric current and takes advantage of for internal reference magnitude of current the comparison, then produces one to use in the signal grid driving circuit's output warning.
This commonly used analogue control method has realized to the peak class control, because the LED light color drifting doesn't allow in many request strict illumination application domain, therefore this method isn't the high quality illumination best solution.
Innovation LED driver The italian law semiconductor proposed the correct satisfy the illumination request the high cost benefit street lighting platform treatment. This plan has the outstanding performance, the superelevation energy efficiency (when capacity load overall energy efficiency is larger than 91%), the complete against expiration management (overflow protection, overvoltage protection and short circuit protection) the get the job done.
This platform by two major part is composed: Power unit and electricity controller. And, the ac current controller is a digital electric current controller. Power circuit's peak power output achieves 130W (48V,2.7A), this electric circuit is constructed from two levels of electric circuits: Based on L6562AT front end power factor adjuster (PFC) and in relation to L6599AT LLC resonance switch. This design's characteristic is as follows: Expansion Europe inputs the alternating voltage scope (177/277 VAC - frequency 45/55 Hz) The superelevation energy efficiency (full load was 93.85%) has avoided to radiator's demand Non-electrolytic capacitor, long-time reliable Conforms to EN61000-3-2 Class-C (exchange overtone), EN55022-Class-B(EMI) and EN60950 double insulates the (SELV) standard