AC-DC LED driver solution for LED general lighting challenges

LED general lighting design engineers face many challenges such as power density, power factor correction (PFC), space limitations, and reliability. These LED lighting design challenges are similar to power supply design challenges. Specifically, LED general lighting has several challenges: because of the total light efficiency requirements and thermal limitations, even low-power applications are important; in many cases, Low power also requires power factor correction and harmonic processing; in space-constrained applications, especially when replacing bulb applications, the drive power density is critical; overall power reliability is important to improve overall lamp life; wide input The supply voltage range should support up to 277 Vac; compatible with traditional specific lighting requirements such as TRIAC dimming. In addition, LED general lighting must comply with evolving standards and safety regulations, such as the US "Energy Star" and the European Union's International Electrotechnical Commission (IEC) requirements.

ON Semiconductor has been providing a wide range of solutions for LED lighting, introducing a variety of products that meet the latest LED lighting standards, including AC-DC power ICs, DC-DC drivers, CCR stabilizers, constant current and constant voltage (CCCV). Control, high voltage FET, rectifier, digital interface, ambient light sensor, protection, power line communication (PLC) modem and more. This article mainly introduces the AC-DC power supply scheme and related circuits for LED lighting, helping engineers to meet the above challenges and design products that meet the requirements of general lighting.

ON Semiconductor LED Lighting Solutions

Figure 1: Application diagram of ON Semiconductor's LED lighting solution

In ON Semiconductor's AC-DC power solution for LED lighting, NCP1010~5 is recommended for lighting applications from 1 to 10 W, and NCP1027/8 is available for 1 to 15 W. These solutions integrate MOS transistors for isolation. And non-isolated applications, support for secondary PWM dimming, analog dimming or dual brightness level dimming, energy efficiency up to 75-80%; 1 to 30 W applications can use LV5026, 5027, 5028, support isolation scheme, typical energy efficiency 85 About 1%; 1 to 40 W recommended to use NCL30000, for primary thyristor dimming, for isolation and non-isolation schemes, isolation scheme energy efficiency 80-85%. The 40 to 150 W is recommended for the NCL30001, which is a continuous conduction mode (CCM) control chip. The typical energy efficiency of the isolation scheme is 85-90%; the NCL30051 is recommended for higher power. Figure 2 is a comparison of output power and energy efficiency of these schemes. The functions and features of these solutions are described in detail below.

Figure 2: Comparison of output power and efficiency of an AC-DC power scheme for LED lighting.