See how the highly integrated low-power LED bulb driver LYTSwitch-0 can help users achieve low-cost design

Recently, Power Integrations (PI) launched a series of highly integrated low-power LED bulb drivers, LYTSwitch-0, which has added a new member to the LYTSwitch family with excellent dimming performance. The efficiency of LYTSwitch-0 devices is over 90%, and it can provide constant current output with an adjustment accuracy better than +/-5% in typical applications. Its power factor is greater than 0.8 at 115 VAC and reaches 0.55 at 230 VAC, which can meet the North American consumer lighting standards of ENERGYSTAR V1 Draft 3, and the European Ecodesign Directive Lot 19 Part 2 standards. It is very suitable for cost-sensitive, non-isolated, non-dimming GU10 bulbs and other space-constrained bulb applications.

The continued decline in LED bulb costs poses challenges to LED drivers

With the general trend of LED lamps replacing incandescent lamps, the cost of LED lamps has always been a sensitive topic. Under the premise of ensuring unchanged performance, the driver, which accounts for 40% of the cost of LED bulbs, is also facing tremendous pressure and challenges. Andrew Smith, product marketing manager of PI, said: "Between 2013 and 2015, through the continuous improvement of processes and technologies, the cost of LED drivers is expected to drop from US$11 to US$7, a cost reduction of nearly 36%." This will be able to meet users' requirements for low cost (Figure 1).

Figure 1 LED bulb price trend

How does PI reduce the cost of LED drivers?

LYTSwitch-0 is a LED driver that is universal for global voltage standards. The voltage range of the input stage is 90~265VAC, which meets the voltage standards of various countries. It also integrates a series of complete protection functions, such as open-loop protection, short-circuit protection, overheat protection, etc. The advantages of high integration make the external circuit very simple. The entire circuit only requires very few external components to meet the user's design requirements. Users can build multiple topologies such as HS/LS (low-side/high-side) buck, buck-boost, flyback, and boost around the device according to actual design requirements. It is the most cost-effective design. Figure 2 is a GU10 LED driver designed using LYTSwitch-0 IC and only 13 components. See RDR-355 for details, for reference by engineers.

Figure 2. Buck-type GU10 LED driver designed using LYTSwitch-0 IC and only 13 components.

In addition to supporting multiple topologies, LYTSwitch-0 also has a strong advantage in output constant current fluctuation. Compared with ordinary LED drivers whose output constant current fluctuation is generally limited to 5%, LYTSwitch-0 can control it within 2% under different voltages and temperatures. This is a great improvement in solving the problem of LED light flicker and greatly reduces the cost of multiple-degree design.

Perhaps many engineers will ask what the price of such a highly integrated chip will be? Andrew Smith, product marketing manager of PI, said: "PI has never fought a price war. The price of a single LYTSwitch-0 chip is definitely not the lowest among its peers, but this series of devices has great advantages in terms of system and overall price. In addition to the tangible material cost, the cost of a product also includes intangible costs such as procurement, inventory, and transportation, which are another important component of the product price." This series of products can be mainly used in low-power fields such as light bulbs, tubes, and adapters.