With the development of LED technology , LED applications have been extended from traditional low-power portable backlights to medium- and high-power indoor lighting , outdoor lighting and flashlight applications. Depending on the driving power supply, LED lighting can usually be divided into AC-DC LED lighting, DC-DC LED lighting power supply and battery-powered LED flashlights. LED lamps and their power are also available. Different, such as 3 W PAR16, 3×2 W PAR20, 10 W/15 W PAR30, 15 W/22 W PAR38, 1 W G13, 3 W GU10, 1 W MR11, 3 W MR16, 3 W/9 W /15 W recessed light, 1 W-3 W reading light, etc. Figure 1: Isolated topology with different power ranges In AC-DC LED lighting applications, low-power LED applications are typically driven at constant current (CC), while constant voltage (CV) functions are protected when the output is open. High-power LED applications may require the addition of PFCs in the circuit. The two-part circuit of AC-DC conversion and LED driving may be in an integral configuration, that is, the two are combined and located in the lighting fixture. A distributed configuration can be used, as shown in Figure 2, to simplify security considerations and increase system flexibility. Figure 2: Distributed configuration of high-power LED drivers From the specific power range of the application, the power solution application of AC-DC LED lighting mainly includes: 1 W-8 W: G13/GU10/PAR16/PAR20 lighting 1) 1 W-8 W AC-DC LED Lighting Application These applications require input voltages from 90 to 264 Vac and 80% efficiency, while providing protection against short-circuit protection, overvoltage protection, and 350 mA, 700 mA constant current for applications including G13, GU10, PAR16, PAR20 And downlights, etc. ON Semiconductor's NCP1015 self-powered monolithic switching regulator can be used in this type of application. This component combines a fixed frequency (65/100/130 kHz) current mode controller with a 700 V high voltage MOSFET to provide all the features needed to build a robust, low cost power supply such as soft start, frequency jitter, short circuit protection, hopping Cycle, maximum peak current set point and dynamic self-powered function (no auxiliary winding required). Figure 3 shows a circuit diagram of the NCP1015 in an isolated 1 W-8 W range AC-DC LED lighting application. It is worth mentioning that the NCP1015 can also be used in non-isolated (high-frequency transformers in the circuit) 1 W-8 W range AC-DC LED lighting applications. Tapped inductors can be used in the circuit to improve MOSFET operation. Duty cycle and improve system performance and circuit performance. Figure 3: Ansemite 8 W LED driver application circuit diagram (input voltage 85 to 264 Vac) 2) 8 W-25 W AC-DC LED Lighting Application The US Department of Energy (DOE) Energy Star (ENERGYSTARTM) Solid State Lighting (SSL) specification states that any power level must be mandatory for PFC. This standard applies to a range of specific products, such as recessed lights, cabinet lights, and desk lamps, where the LED driver power factor for residential applications must be greater than 0.7, and for commercial applications greater than 0.9. However, this standard is a voluntary standard, that is, you can choose not to comply or comply. In the 8 W-25 W AC-DC LED lighting application, we consider two cases, one is that there is no power factor requirement in the application, that is, there is no need for a PFC controller, and the other is to require a PFC controller. In applications that do not use PFC, we assume an input voltage specification of 90~132 Vac or 180~264Vac (or universal input) with 85% efficiency, providing protection features such as short-circuit protection and open-circuit protection. The output current is 350 mA, 700. mA and 1 A constant current, corresponding to the NCP1028 or NCP1351 from ON Semiconductor. Among them, the NCP1028 is an enhanced single-chip switching regulator that provides several watts to 15 watts of output power for general-purpose mains input applications. The NCP1028's on-resistance is lower than the NCP101x, providing 800 mA peak current, with many features of the NCP101x, plus over-power protection, built-in slope compensation, and input undervoltage protection. The NCP1351 is a fixed on-time, variable off-time pulse width modulation (PWM) controller for cost-effective low-power off-line flyback switching power applications. This component supports frequency reversal and features latch-up inputs, natural frequency jitter, negative current sensing, and extended supply voltage range. Figure 4 shows the 8 W-25 W LED lighting solution based on the NCP1351 at 90 to 264 Vac input. Figure 4: Schematic diagram of an 8 W to 25 W AC-DC LED lighting application circuit using the NCP1351. In the 8 W-25 W AC-DC LED lighting application requiring PFC, the input voltage specification is 90 to 264 Vac, the power factor is higher than 0.9, the performance is 80%, short circuit and over power protection are provided, and the output current is also 350 mA. Different options such as 700 mA and 1 A. In this type of application, ON Semiconductor's NCP1607 or NCP1608 PFC controllers can be used. The NCP1607 is a cost-effective, critical conduction mode (CrM) PFC controller. This component is fully compatible with industry standard pins and simplifies engineer design. Features such as adjustable overvoltage protection (OVP) and open loop protection also enhance design flexibility and robustness. Figure 5 shows the LED lighting application for the NCP1607/NCP1608 at 85 to 135 Vac or 185 to 264 Vac input. Figure 5: Schematic diagram of an 8 W-25 W AC-DC LED lighting application using the NCP1607/8 PFC controller 3) AC-DC LED lighting applications with power above 50 W AC-DC LED applications with powers from 50 W to 300 W are widely used in street lighting and high-power area lighting applications. Different LED drive schemes are available, assuming an input voltage specification of 90 to 264 Vac and a power factor greater than 0.95 The performance is 90%. These applications can be adapted to different application requirements by: NCP1652: Improved single-stage PFC NCP1607/8+NCP1377: Critical Conduction Mode PFC+ Quasi-Resonant Current Mode PWM NCP1607/8+NCP1396: Critical Conduction Mode PFC+ Half-Bridge Resonant LLC NCP1901: The latest two-stage (PFC + higher efficiency half-bridge resonant LLC) For example, in a 50 W-150 W AC-DC LED application, either an improved single-stage PFC controller such as the NCP1652 or a NCP1607/8 PFC controller and NCP1377 quasi-resonant (QR) mode PWM can be used. Controller. Among them, the NCP1377 combines a true current mode modulator and demagnetization detector to ensure complete CrM operation under any load/line conditions and to ensure the lowest leakage voltage switching (quasi-resonant operation). The NCP1652 drives signals with programmable dead time and supports active clamping or synchronous rectification for optimum performance. This component has protection features such as input undervoltage protection, overvoltage protection, and overcurrent protection. It supports frequency jitter, skip cycle, and critical conduction mode (CrM)/discontinuous conduction mode (DCM) operation. A schematic of a 50 W-150 W AC-DC LED scheme based on the NCP1652 with 85 to 135 Vac or 185 to 264 Vac input is shown in Figure 6. Figure 6: 50 W-150 W AC-DC LED Solution Using the NCP1652 Single-Segment PFC Controller AC-DC LED lighting applications with more than 50 W power require high-efficiency LED power supplies, which require high-efficiency LED lighting topologies, often moving from a flyback topology to a resonant half-bridge topology to maximize zero-voltage switching. The advantages of (ZVS) technology. NCP1396 and NCP1901 are high-performance half-bridge resonance solutions for LED power supplies developed by ON Semiconductor. Figure 7 shows the latest PFC+resonant half-bridge LED driver solution based on the NCP1901 with an input voltage of 90 to 264 Vac and a power of 100 W to 300 W, with the half-bridge operating at a fixed frequency and a fixed duty cycle for reducing Switching loss. Figure 7: 100W-300 W AC-DC LED Lighting Solution with NCP1901 2, DC-DC LED lighting solution Among them, in the 1 W-3 W DC-DC LED lighting application, ON Semiconductor's CAT4201 step-down LED driver can be used. This module is compatible with 12 V and 24 V systems and provides 350 mA LED drive current. Driving 7 series LEDs in a 24 V system with up to 94% efficiency. This component uses a patented switch control architecture to help reduce system cost, support CrM work and improve performance. The CAT4201 also offers comprehensive protection features such as current limiting, thermal protection and LED open circuit protection. A schematic of the circuit in this 1 W-3 W DC-DC LED application is shown in Figure 8. Figure 8: 1 W-3 W DC-DC LED Solution with CAT4201 And in the DC-DC boost LED application with a power range of 1 W-20 W, use ON Semiconductor's NCP3065/6 or NCV3065/6 (automotive application version) buck, boost, single-ended primary inductor converter (SEPIC) and inverter multimode LED driver, and select the boost circuit mode. In addition, ON Semiconductor's NCP1034 synchronous buck PWM controller can be used in DC-DC buck LED applications with power ranges from 20 W to 60 W. 3, LED flashlight drive solution Figure 9: LED flashlight boost and buck solution with NCP1421 and NCP1529 4, summary (Editor: Zeng Cong) Medium Voltage Soft Starter,High Voltage Soft Starter,10Kv Voltage Soft Starter,6Kv Voltage Soft Starter Jinan Xinyuhua Energy Technology Co.,Ltd , https://www.xyhenergy.com
1, AC-DC LED lighting solutions
ON Semiconductor offers a wide range of off-line controllers and power factor correction (PFC) controllers for AC-DC power-provided LED lighting applications, with different LED applications for isolation and non-isolation requirements. In isolation applications where there is no physical electrical connection between the AC line voltage and the LED, common topologies are flyback and dual inductor plus single capacitor (LLC) half-bridge resonance. Different topologies are suitable for different power ranges or for meeting special design requirements. For example, the flyback topology is the standard choice for medium to low power applications of less than 100 W, while the LLC half-bridge topology is the preferred solution for high power and high efficiency.
8W -25 W: PAR30/PAR38 lighting
50 W-300 W: area lighting
Commonly used in LED lighting applications powered by DC-DC power supplies include 1 W-3 W MR11/MR16 step-down LED bulbs, 1 W-20 W boost LED driver and 20 W-60 W high power LED driver.
Flashlight DC-DC LED lighting solutions include both boost and buck. The NCP1421 step-up DC-DC converter with true shutdown can be used in a 1 W-3 W step-up DC-DC LED flashlight application, while the NCP1529 low-dropout can be used in a 1 W-3 W step-down LED flashlight application. The pressure converter, the application diagram of the two is shown in Figure 9.
ON Semiconductor is the world's leading provider of high performance, high performance silicon solutions, offering LED lighting drivers and PFC solutions ranging from 1 to hundreds of watts. Whether using AC-DC power supplies, DC-DC power supplies, or LED lighting drivers for batteries used in LED flashlights, ON Semiconductor can provide customers with low cost, cost effective, high performance or the choice of PFC. Different requirements for LED lighting driver solutions.