如何为线性LED模块选择合适的LED驱动器？

With the fast growth of LED lighting technology and new standards from the Zhaga Consortium, linear LED modules are now widely used in commercial lighting, building decoration, and industrial settings because they provide even light, can be installed in different ways, and can be easily replaced.

However, their performance and lifespan heavily depend on the compatibility of the LED driver—an unsuitable driver may result in uneven brightness, low energy efficiency, or even module damage.

Faced with diverse driver types like constant current, constant voltage, and linear options, engineers and procurement professionals must accurately select drivers based on the voltage, current requirements, and environmental conditions of linear LED modules.

This article provides a systematic selection guide covering core parameters and topology structures, helping you achieve synergistic optimization between LED linear modules and LED drivers.

What Is an LED Driver?

一个 LED 驱动器 is an electronic device specifically designed to power light-emitting diodes (LEDs). Its primary function is to convert alternating current (AC) into the direct current (DC) required by LEDs, while precisely controlling current and voltage to ensure the LEDs operate normally and steadily.

Beyond supplying power, LED drivers must precisely regulate current and voltage. LEDs are highly sensitive to fluctuations in these parameters, where even minor deviations can cause damage or performance degradation. Consequently, LED drivers demand advanced technical specifications and sophisticated control capabilities.

When selecting an LED driver, comprehensive consideration must be given to factors such as the specific LED luminaire type, power requirements, and operating environment to ensure the most suitable driver type is chosen.

Within LED lighting systems, the LED driver serves not only as the “energy hub” supplying stable, reliable power to LEDs but also as a critical factor safeguarding LED performance and lifespan. A high-quality LED driver significantly enhances the luminous efficiency, stability, and reliability of LED fixtures while reducing failure rates and maintenance expenses. This delivers users a more energy-efficient, environmentally friendly, comfortable, and convenient lighting experience.

Constant Current (CC) vs. Constant Voltage (CV) Drivers

Depending on different application scenarios and requirements, LED drivers come in various types. Based on output mode, they can be categorized into constant current drivers and constant voltage drivers.

• ‌Constant Current Advantages‌: Compensates for LED forward voltage variations with temperature, extending lifespan.

• ‌Constant Voltage Limitations‌: Requires additional current control circuit design, offering lower cost but higher risk.

When selecting an LED driver, comprehensive consideration of factors such as the type of LED fixture, power requirements, and operating environment is essential to ensure the most suitable driver type is chosen.

Let’s delve into the differences between constant current and constant voltage power supplies:

‌Constant Current 发光二极管 Drive‌

Outputs a steady current while voltage varies with load. Voltage is dynamically adjusted via a current feedback loop to maintain current stability. For instance, when LED chip temperature rises and resistance decreases, the power supply automatically reduces voltage to sustain constant current.

‌Constant-current drivers are suitable for driving single or multiple LED strings. They enable precise current control, preventing brightness drift and thermal runaway, making them an ideal choice for LED lighting. Constant-current power supplies strictly prohibit open-circuit loads (e.g., broken LEDs) but can protect circuits by adjusting voltage during short circuits.

‌Constant Voltage 发光二极管 Drive

Output voltage remains constant while current varies with load. Voltage feedback loops regulate output. When directly driving LEDs, a series current-limiting resistor is required. However, voltage fluctuations may cause current instability, leading to LED overheating or burnout.

Constant-voltage power supplies are primarily used in scenarios requiring parallel connections, such as LED strips. They necessitate resistor pairing and demand high voltage stability. Constant-voltage power supplies must never experience complete load short circuits or open circuits, as this may burn out the LED lights.

In summary, constant-current power supplies offer greater reliability in LED module applications, while constant-voltage power supplies require careful design and protective measures.

Further Reading: “恒压与恒流：哪个 LED 灯条最适合商业项目？”

Key Factors When Choosing an LED Driver

1. Electrical Match

When selecting the input voltage for an LED driver, ensure it matches the local grid voltage while accounting for voltage fluctuations. Grid voltage is not absolutely stable and may vary by ±10%.

For example, in a region with a nominal 220V supply, actual voltage may range from 198V to 242V. Therefore, the selected power supply’s input range must cover these fluctuations; otherwise, it may fail to operate properly or become damaged.

Input voltage is typically AC (alternating current), and the voltage used varies by country. For instance, the United States and Canada use 120V, Japan uses 110V, and most European countries use 230-240V. Below is a reference table of voltages used in different countries:

大多数 National V电压 References

国家	电压	Frequency
中国	220V	50Hz
日本	100V	50/60Hz
Korea	100V	60Hz
Hong Kong	200V	50Hz
泰	220V	50Hz
印度尼西	220V	50Hz
Canada	120V	60Hz
Argentina	220V	50Hz
Mexico	120V	60Hz
美国	120V	60Hz
Guam	110V	60Hz
Italy	220V	50Hz
Germany	220V	50Hz
England	240V	50Hz
France	127V, 220V	50Hz
Greece	220V	50Hz
Sweden	120V, 127V, 220V	50Hz
Netherlands	220V	50Hz
Norway	230V	50Hz
Denmark	220V	50Hz
Switzerland	220V	50Hz
Finland	230V	50Hz
Belgium	220V	50/60Hz
Spain	127V, 220V	50Hz
Austria	220V	50Hz

The output voltage of the LED driver must match the voltage of the LED linear module, as shown below: The 560×24 linear LED module designed by SignliteLED is labeled with a voltage of DC44V. Based on this rated voltage, the corresponding Leifu FMR040YS power supply can be selected, whose output voltage ranges from 40V to 130V.

2. Power Rating & Efficiency

The rated power refers to the maximum power an LED driver can deliver under stable operating conditions. The driver’s rated power must match the power requirements of the LED luminaire. When selecting a driver, choose one with a power rating slightly higher than the luminaire’s power to ensure a margin and enhance stability. For example, a 35W LED linear module should be paired with a 35-40W LED driver to avoid efficiency drops caused by overloading or underloading.

The efficiency of an LED driver is the ratio of its output power to input power, calculated as Efficiency (η) = (Output Power / Input Power) × 100%. For instance, if 100W of electrical energy is input and 90W of power is output, the efficiency is 90%. High-quality drivers achieve efficiencies exceeding 90%. Linear module drivers from brands like Tridonic, Osram, and Lifud typically operate around 91% efficiency.

Additionally, under identical load conditions, LED drivers operating at higher currents generally exhibit slightly higher efficiency than those at lower currents. For instance, a 350 mA driver may be 1-2% more efficient than a 100 mA driver.

When selecting a high-efficiency driver, standby power consumption must also be considered. Standby power refers to the electrical energy continuously consumed by the LED driver to maintain basic functions when the load is disconnected. Even without a load, internal circuitry incurs no-load losses (e.g., transformer heating). The EU ErP Directive mandates standby power consumption ≤0.5W for LED drivers, with premium drivers achieving as low as 0.3W.

Application Recommendations:

Selecting an LED driver with a rated power equal to or greater than the LED linear module ensures more stable and reliable operation.

Additionally, using high-efficiency drivers helps users save electricity costs, reduce equipment heat generation and environmental impact, and, to some extent, lower the driver’s own power consumption and heat output. For industrial applications, prioritize drivers with PF ≥ 0.9 and efficiency ≥ 90%. For residential applications, focus on light-load efficiency (e.g., efficiency > 85% at 20% load) and low standby power consumption (≤ 0.5W).

3. Dimming Compatibility

Linear LED modules typically employ constant-current drivers, whose brightness adjustment relies on precise control from dimmable LED drivers. Currently, linear dimming drivers primarily include the following types:

• DALI 调光: DALI (Digital Addressable Lighting Interface) is a digital lighting control standard that enables precise control of lighting fixtures via digital signaling protocols. Each luminaire or driver unit possesses a unique address, supporting individual or grouped control. Compared to 0-10V or PWM dimming methods, it is better suited for complex environments such as hotels and museums.

• 3-in-1 Dimming: 3-in-1 dimming is an integrated lighting control solution combining multiple dimming technologies, typically referring to LED driver technology supporting 0-10V dimming, PWM (Pulse Width Modulation) dimming, and resistor (Rx) dimming simultaneously.

• a) 0-10V Dimming: Directly controls the drive current via an analog voltage signal (0-10V DC), classified as analog dimming. Brightness adjustment relies on voltage variation without requiring high-frequency switching. The output current is controlled by a 0-10V DC signal, turning the fixture off at 0V and reaching 100% brightness at 10V. Suitable for flicker-free, long-distance control scenarios.

• b) PWM Dimming: Adjusts duty cycle via high-frequency switching, requiring support for frequencies ≥1 kHz to minimize flicker. PWM is a digital dimming method, essentially pulse control alternating between “on” and “off” states. It suits scenarios requiring high-precision, low-cost dimming.

• c) Adjustable Resistor (Rx) Dimming: Changes circuit resistance via a potentiometer to regulate output current and control brightness. Characteristics: Simple circuitry but lower precision, commonly used in low-cost solutions.

• TRIAC 调光: TRIAC dimming is a technique that controls current magnitude by adjusting the conduction angle of a triac (silicon-controlled rectifier). Its core principle involves altering the conduction time (phase angle) of each half-wave of AC power to adjust the effective value of the output voltage, thereby regulating load power and brightness. It is applied in scenarios requiring simple installation without complex wiring.

4. Certifications & Safety

Certification and safety of LED drivers are critical to ensuring product compliance, market access, and user safety. Major global markets enforce mandatory certifications for LED drivers, with different countries requiring distinct safety certifications such as the EU’s CE, Germany’s TÜV, and the US’s UL.

Selecting drivers compliant with local certifications ensures both safety and legal compliance. This safeguards products against regulatory non-compliance risks such as cargo detention, fines, or market bans. Therefore, certification screening and safety design optimization significantly enhance the overall reliability of lighting systems.

5. Environment & Lifespan

The stability and lifespan of LED drivers are directly influenced by the operating environment, making them critical factors in determining the overall reliability of LED systems. In high-temperature, humid, or dusty conditions, internal driver components accelerate aging—such as electrolyte drying in electrolytic capacitors or oxidation of metal parts—leading to efficiency loss or failure.

When subjected to prolonged high temperatures, the lifespan of an LED driver may shrink from its theoretical 50,000 hours to below 10,000 hours. Additionally, grid voltage fluctuations and frequent switching operations can impact the driver, further shortening its service life.

Therefore, selecting appropriate installation environments (e.g., well-ventilated, moisture-proof, dust-proof) and employing high-quality LED drivers can significantly extend system lifespan and reduce maintenance costs. Optimizing operating conditions not only enhances driver performance but also ensures long-term stable operation of LED equipment, maximizing economic benefits.

How Many Linear LED Modules Can You Run with a Driver?

In most professional lighting systems, linear LED modules are driven using constant current technology. This design ensures consistent current flow to each module, resulting in uniform brightness, stable color temperature, and extended lifespan.

So, how many linear modules can a single constant current driver power? This depends on the operating voltage of the modules and the output voltage range of the driver.

1. Identify the Driver’s Fundamental Parameters

Two critical specifications for constant current drivers are

• Output Current (mA): e.g., 350mA, 500mA, 700mA, 1050mA, indicating the current each module will carry.
• Output voltage range (V): e.g., DC25–54V, DC176–280V, which determines the maximum total voltage for series-connected modules.

LED linear modules must be connected in series within a constant-current system, where the total voltage equals the sum of each module’s voltage. Therefore, the driver’s output voltage range directly determines the maximum number of modules you can connect in series.

2. Calculating the Number of Series Modules

Using the most common 350mA constant-current driver (40–120V output) as an example:

If a single module (560mm) has a forward voltage (VF) of 44V, then approximately 2.7 modules can be connected in series: 120V ÷ 44V ≈ 2.7 modules. In practice, a 10% safety margin is recommended, making 2 modules the optimal configuration.

The system will operate stably as long as the total module voltage falls within the driver’s output range. If the voltage is below the minimum startup voltage (e.g., 36V), the driver will fail to activate. If it exceeds the upper limit (e.g., over 120V), the driver will trigger overload protection or exhibit flickering.

3. Efficiency and Thermal Design Considerations

LED drivers do not operate efficiently across their entire voltage range. It is generally recommended to maintain the total module voltage within 70%–90% of the driver’s rated output.

For example, a DC40–120V driver operates optimally within approximately 44–110V. At this range, the driver achieves peak efficiency, generates less heat, and extends module lifespan.

Additionally, when connecting multiple module groups in series within a single fixture, a multi-driver segmented power supply design is recommended. This ensures consistent brightness across all modules, simplifies maintenance, and facilitates power balancing.

4. Optimizing Configuration Based on Project Scenarios

During the project design phase, consider the following guidelines:

• Low-power modules (<10W): Suitable for 4–6 series connections, requiring only 200mA or 275mA drivers.
• Medium-power modules (10–15W): Recommended 2–3 series connections, with 350mA or 500mA drivers offering greater stability.
• High-power modules or COB modules: Typically only 1–2 in series; select drivers with high-voltage output capabilities.

The forward voltage (VF) varies slightly across brands and LED packages. Therefore, always consult the module’s datasheet before selection and precisely match it to the driver’s output range.

Determining how many LED linear modules a driver can power hinges on understanding:

• The voltage stacking pattern of modules in series under constant current drive;
• The driver’s voltage range and safety margin;
• The efficiency and thermal balance of the entire system.

Understanding these three points enables quick identification of the optimal driver-module combination.

At SignliteLED, we provide customized constant-current module solutions based on customer-supplied driver current parameters, module power requirements, and fixture dimensions. This ensures every linear lighting system operates under optimal electrical conditions.

Common Mistakes to Avoid

When using LED drivers with linear LED modules, special attention must be paid to electrical compatibility, mounting methods, heat dissipation, and signal control to ensure stable system operation.

电压和电流

The driver’s output current must match the linear module’s operating current. The driver’s output current must be ≥ the module’s total current (e.g., a 500mA module requires a driver rated at 500mA or higher) to prevent overloading and overheating. Exceeding the module’s maximum current rating risks burning out the LED chips.

Linear modules typically feature low-voltage designs (DC 20V/48V). Ensure the LED module’s operating voltage falls within the power supply’s output range. If the power supply’s output voltage is lower than the module’s voltage, it may cause the LED’s forward voltage (Vf) to drop, resulting in flickering.

Constant Current/Constant Voltage Selection

Most linear modules use constant current drive (100-400mA), while some require constant voltage drive (DC12V/24V/48V). Select based on actual conditions. Mixing constant voltage and constant current drives may cause uneven brightness or damage modules.

Installation and Wiring

Correctly connect input and output wires; reverse polarity risks damaging the driver. Series or parallel installation of linear modules requires professional installation to prevent non-illumination or module damage due to incorrect connections.

散热设计

Linear modules must be mounted on aluminum substrates or heat sinks to prevent light decay from prolonged full-power operation. For outdoor or humid environments, select modules and drivers with IP65 or higher protection ratings. Driver housings must be rust-resistant (e.g., aluminum alloy).

调光兼容性

Ensure drivers support PWM dimming protocols (e.g., 0-10V, DALI) to prevent flickering caused by incompatible dimmers.

Implementing these measures effectively prevents compatibility issues between LED linear modules and drivers, extending system lifespan.

结论

The above outlines several key factors to prioritize when selecting LED drivers for linear modules. We trust this information will prove helpful to you.

SignliteLED specializes in innovative lighting technology, driving global standardization of lighting components. Our developed LED线性模块 comply with Zhaga standards, featuring high luminous efficacy, long-lasting durability, and flexible installation. Current product offerings are suitable for various applications, including LED linear lights and LED tri-proof lights.