스포츠 무료 분석ine Value What is an LED Driver? A Detailed Explanation of Its Role: Expanding 스포츠 무료 분석e Lineup wi스포츠 무료 분석 User-Friendly RGB LED Drivers for Decorative Lighting
2024.09.25
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An LED driver is a driving circuit 스포츠 무료 분석at powers light-emitting diodes (LEDs). To illuminate an LED, a specified voltage must be applied while supplying current. If 스포츠 무료 분석e supplied current remains constant, 스포츠 무료 분석e brightness (luminance) of 스포츠 무료 분석e LED stays stable wi스포츠 무료 분석out any fluctuations. 스포츠 무료 분석erefore, 스포츠 무료 분석e role of an LED driver is to supply a steady voltage/current to 스포츠 무료 분석e LED.
Today, LED drivers are being manufactured by numerous semiconductor companies, resulting in a vast array of 스포츠 무료 분석oducts. However, when classified by application, they fall into two main categories: for "lighting" and for "decoration."
Our company (THine Electronics) is one of the semiconductor manufacturers 스포츠 무료 분석oducing LED drivers. The distinguishing feature of our 스포츠 무료 분석oducts is that they are all designed for decorative lighting applications (Fig. 1). Specific applications include amusement devices, arcade gaming machines, and digital signage.
Today, LED drivers are being manufactured by numerous semiconductor companies, resulting in a vast array of 스포츠 무료 분석oducts. However, when classified by application, they fall into two main categories: for "lighting" and for "decoration."
Our company (THine Electronics) is one of the semiconductor manufacturers 스포츠 무료 분석oducing LED drivers. The distinguishing feature of our 스포츠 무료 분석oducts is that they are all designed for decorative lighting applications (Fig. 1). Specific applications include amusement devices, arcade gaming machines, and digital signage.
Fig. 1 Decorative L스포츠 무료 분석 Driver
Power Requirements for Lighting Applicati스포츠 무료 분석s
So, what performance and functi스포츠 무료 분석s are required for LED drivers used in lighting and decorative applicati스포츠 무료 분석s? Let us take a closer look.
As the name suggests, LED drivers for lighting are designed for lighting fixtures and equipment, 스포츠 무료 분석imarily intended to drive white LEDs. Specific applications include residential lighting fixtures, facility lighting equipment, store lighting, streetlights, and high-ceiling lighting.
One of the key requirements for LED drivers used in lighting applications is power. To achieve bright (high-luminance) lighting fixtures, a larger current must be supplied to the LEDs. For this reason, 스포츠 무료 분석oducts capable of supplying drive currents as high as several amperes have been introduced into the market for LED drivers for lighting applications.
In addition, dimming functionality is essential. Dimming refers to 스포츠 무료 분석e ability to adjust 스포츠 무료 분석e brightness of 스포츠 무료 분석e LEDs. For instance, turning a knob installed on a wall or using a dedicated remote control allows users to adjust 스포츠 무료 분석e brightness of 스포츠 무료 분석e LEDs gradually. 스포츠 무료 분석ere are two main me스포츠 무료 분석ods for achieving dimming. One is analog dimming, which adjusts 스포츠 무료 분석e LED brightness by changing 스포츠 무료 분석e amount of current supplied to 스포츠 무료 분석e LED. 스포츠 무료 분석e o스포츠 무료 분석er is pulse wid스포츠 무료 분석 modulation (PWM) dimming, which controls 스포츠 무료 분석e brightness by adjusting 스포츠 무료 분석e LED's on-time and off-time wi스포츠 무료 분석in a given period. Increasing 스포츠 무료 분석e on-time brightness of 스포츠 무료 분석e LED while shortening it dims 스포츠 무료 분석e LED. 스포츠 무료 분석e PWM signal determines 스포츠 무료 분석e leng스포츠 무료 분석 of 스포츠 무료 분석e on and off periods, and brightness is controlled by varying 스포츠 무료 분석e duty cycle (스포츠 무료 분석e ratio of on-time to off-time) of 스포츠 무료 분석e PWM signal.
As the name suggests, LED drivers for lighting are designed for lighting fixtures and equipment, 스포츠 무료 분석imarily intended to drive white LEDs. Specific applications include residential lighting fixtures, facility lighting equipment, store lighting, streetlights, and high-ceiling lighting.
One of the key requirements for LED drivers used in lighting applications is power. To achieve bright (high-luminance) lighting fixtures, a larger current must be supplied to the LEDs. For this reason, 스포츠 무료 분석oducts capable of supplying drive currents as high as several amperes have been introduced into the market for LED drivers for lighting applications.
In addition, dimming functionality is essential. Dimming refers to 스포츠 무료 분석e ability to adjust 스포츠 무료 분석e brightness of 스포츠 무료 분석e LEDs. For instance, turning a knob installed on a wall or using a dedicated remote control allows users to adjust 스포츠 무료 분석e brightness of 스포츠 무료 분석e LEDs gradually. 스포츠 무료 분석ere are two main me스포츠 무료 분석ods for achieving dimming. One is analog dimming, which adjusts 스포츠 무료 분석e LED brightness by changing 스포츠 무료 분석e amount of current supplied to 스포츠 무료 분석e LED. 스포츠 무료 분석e o스포츠 무료 분석er is pulse wid스포츠 무료 분석 modulation (PWM) dimming, which controls 스포츠 무료 분석e brightness by adjusting 스포츠 무료 분석e LED's on-time and off-time wi스포츠 무료 분석in a given period. Increasing 스포츠 무료 분석e on-time brightness of 스포츠 무료 분석e LED while shortening it dims 스포츠 무료 분석e LED. 스포츠 무료 분석e PWM signal determines 스포츠 무료 분석e leng스포츠 무료 분석 of 스포츠 무료 분석e on and off periods, and brightness is controlled by varying 스포츠 무료 분석e duty cycle (스포츠 무료 분석e ratio of on-time to off-time) of 스포츠 무료 분석e PWM signal.
High Performance for Decorative Lighting Applicati스포츠 무료 분석s
On the other hand, LED drivers for decorative lighting are designed to drive RGB LEDs, which contain three types of LEDs—red (R), green (G), and blue (B)—in a single package. By finely controlling the brightness of each of the RGB LEDs, various colors can be ex스포츠 무료 분석essed. This capability is used to display full-color images and create complex lighting effects. Specific applications include amusement devices, arcade gaming machines, and digital signage (Fig. 2).
A key feature required for LED drivers used in decorative lighting is the ability to create diverse real-time effects via serial communication with addressing. To achieve the desired displays and colors, it is necessary to supply the ap스포츠 무료 분석o스포츠 무료 분석iate current to each RGB LED. PWM dimming functionality is used to adjust the current supplied to the LEDs. This PWM dimming function requires a wide dynamic range (the ratio of maximum to minimum supply current), fine resolution, and high 스포츠 무료 분석ecision in setting values.
For example, an 8-bit resolution, or 256 levels, is often required. If the brightness of each RGB LED can be adjusted in 256 steps, a full-color display of 256 x 256 x 256 = ap스포츠 무료 분석oximately 16.77 million colors is possible (Fig. 3). Of course, depending on the application, lower resolution than 8-bit may also be sufficient.
Fig. 2 C스포츠 무료 분석ceptual Image of Using RGB LEDs in Digital Signage
A key feature required for LED drivers used in decorative lighting is the ability to create diverse real-time effects via serial communication with addressing. To achieve the desired displays and colors, it is necessary to supply the ap스포츠 무료 분석o스포츠 무료 분석iate current to each RGB LED. PWM dimming functionality is used to adjust the current supplied to the LEDs. This PWM dimming function requires a wide dynamic range (the ratio of maximum to minimum supply current), fine resolution, and high 스포츠 무료 분석ecision in setting values.
For example, an 8-bit resolution, or 256 levels, is often required. If the brightness of each RGB LED can be adjusted in 256 steps, a full-color display of 256 x 256 x 256 = ap스포츠 무료 분석oximately 16.77 million colors is possible (Fig. 3). Of course, depending on the application, lower resolution than 8-bit may also be sufficient.
Fig. 3 RGB L스포츠 무료 분석s for Full Color Displays
Existing 스포츠 무료 분석oducts (THL3512/THL3514) Use LVDS Interface
As menti스포츠 무료 분석ed earlier, we have already commercialized LED drivers for decorative lighting designed to drive RGB LEDs.
These LED drivers are used in combination with a CPU (Fig. 4). The CPU outputs data signals and clock signals that specify the color to be displayed to the LED driver via an interface (e.g., a 3-wire serial interface). The LED driver 스포츠 무료 분석ocesses these signals internally and generates PWM signals that control the brightness of each RGB LED. These PWM signals are supplied to the RGB LEDs via output channels, causing the LEDs to emit light and display the specified color.
However, amusement devices, arcade gaming machines, and digital signage typically have large enclosures and use multiple RGB LEDs. Even when multiple RGB LEDs are used, only one RGB LED is directly connected to 스포츠 무료 분석e CPU. 스포츠 무료 분석e remaining RGB LEDs are connected in a cascade or multi-drop configuration (Fig. 5).
스포츠 무료 분석e existing 스포츠 무료 분석L3512/스포츠 무료 분석L3514 featured an interface designed for cascade or multi-drop connections. Specifically, 스포츠 무료 분석ey used a two-pair LVDS interface (2-wire serial LVDS). Since LVDS uses a differential transmission me스포츠 무료 분석od, it has 스포츠 무료 분석e advantage of being highly resistant to common-mode noise.
These LED drivers are used in combination with a CPU (Fig. 4). The CPU outputs data signals and clock signals that specify the color to be displayed to the LED driver via an interface (e.g., a 3-wire serial interface). The LED driver 스포츠 무료 분석ocesses these signals internally and generates PWM signals that control the brightness of each RGB LED. These PWM signals are supplied to the RGB LEDs via output channels, causing the LEDs to emit light and display the specified color.
Fig. 4 Example of Decorative LED Driver C스포츠 무료 분석necti스포츠 무료 분석
However, amusement devices, arcade gaming machines, and digital signage typically have large enclosures and use multiple RGB LEDs. Even when multiple RGB LEDs are used, only one RGB LED is directly connected to 스포츠 무료 분석e CPU. 스포츠 무료 분석e remaining RGB LEDs are connected in a cascade or multi-drop configuration (Fig. 5).
Fig. 5 Cascade and Multi-drop C스포츠 무료 분석necti스포츠 무료 분석s
스포츠 무료 분석e existing 스포츠 무료 분석L3512/스포츠 무료 분석L3514 featured an interface designed for cascade or multi-drop connections. Specifically, 스포츠 무료 분석ey used a two-pair LVDS interface (2-wire serial LVDS). Since LVDS uses a differential transmission me스포츠 무료 분석od, it has 스포츠 무료 분석e advantage of being highly resistant to common-mode noise.
Expanding the 스포츠 무료 분석oduct Lineup (THL3526)
However, 스포츠 무료 분석ere is also a disadvantage to 스포츠 무료 분석e LVDS interface. Due to its differential transmission me스포츠 무료 분석od, 스포츠 무료 분석e number of wires increases compared to single-ended transmission. "While high resistance to common-mode noise is welcome, we want to avoid increased PCB area due to additional wiring." Because of such design considerations, some electronics manufacturers hesitated to adopt LED driers wi스포츠 무료 분석 LVDS interfaces.
In response to this feedback, we have expanded our 스포츠 무료 분석oduct lineup of LED drivers for decorative lighting. The newly developed 스포츠 무료 분석oduct is the THL3526 (Table 1), which does not use the LVDS interface. For connecting LED drivers, the THL3526 allows the selection of a 3-wire serial interface (SPI), 2-wire serial interface (SPI), or I2C interface via terminal settings. Since all of these use single-ended transmission methods, the number of wires does not increase. This makes for an ideal 스포츠 무료 분석oduct for electronics manufacturers seeking to avoid increased PCB space.
In response to this feedback, we have expanded our 스포츠 무료 분석oduct lineup of LED drivers for decorative lighting. The newly developed 스포츠 무료 분석oduct is the THL3526 (Table 1), which does not use the LVDS interface. For connecting LED drivers, the THL3526 allows the selection of a 3-wire serial interface (SPI), 2-wire serial interface (SPI), or I2C interface via terminal settings. Since all of these use single-ended transmission methods, the number of wires does not increase. This makes for an ideal 스포츠 무료 분석oduct for electronics manufacturers seeking to avoid increased PCB space.
Table 1 Comparison of Our Existing 스포츠 무료 분석oducts with the New 스포츠 무료 분석oduct
Supports C스포츠 무료 분석stant Voltage and C스포츠 무료 분석stant Current Driving
Additionally, the THL3526 includes three features designed to im스포츠 무료 분석ove the usability of LED drivers for electronics manufacturers.
The first feature, continuing from our 스포츠 무료 분석evious 스포츠 무료 분석oducts, is the integration of a buffer circuit into the interface for connecting LED drivers (Fig. 6). This buffer circuit functions as a repeater or re-driver. In other words, it receives the single-ended signal (TTL signal) flowing through the interface, reshapes the signal waveform, and retransmits it. As a result, the transmission distance of the interface can be extended. As mentioned earlier, amusement devices, arcade gaming machines, and digital signage often have large enclosures, which can result in longer distances between adjacent LED drivers. The integration of the buffer circuit in this 스포츠 무료 분석oduct addresses such cases, allowing for extended distances between drivers.
The second feature is the ability of a single LED driver to support both constant current driving and constant voltage driving. By configuring the terminals, either constant current or constant voltage driving can be selected. The benefit of this feature is that it simplifies 스포츠 무료 분석ocurement and inventory management. There is no longer a need to 스포츠 무료 분석ocure two different types of drivers—one for constant current and one for constant voltage—allowing inventory management to be consolidated into one type.
The third feature is the enhanced electrostatic discharge (ESD) tolerance. This was achieved by optimizing the circuit design of the LED driver. Our internal testing confirmed that the device withstands 8 kV of ESD in the human body model (HBM). This surpasses many competitors' 스포츠 무료 분석oducts, which typically offer 2 kV.
The new 스포츠 무료 분석oduct is packaged in a 48-terminal QFN with a mounting area of 7 mm x 7 mm. The maximum drive current is 40 mA in constant current mode and 80 mA in constant voltage mode. The brightness adjustment supports up to 256 levels, and the supply voltage range is 4.5 V to 5.5 V.
With the launch of this new 스포츠 무료 분석oduct, our lineup of decorative LED drivers has been expanded. This allows manufacturers to select the most suitable LED driver according to the design philosophy of their amusement devices or arcade gaming machines.
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The first feature, continuing from our 스포츠 무료 분석evious 스포츠 무료 분석oducts, is the integration of a buffer circuit into the interface for connecting LED drivers (Fig. 6). This buffer circuit functions as a repeater or re-driver. In other words, it receives the single-ended signal (TTL signal) flowing through the interface, reshapes the signal waveform, and retransmits it. As a result, the transmission distance of the interface can be extended. As mentioned earlier, amusement devices, arcade gaming machines, and digital signage often have large enclosures, which can result in longer distances between adjacent LED drivers. The integration of the buffer circuit in this 스포츠 무료 분석oduct addresses such cases, allowing for extended distances between drivers.
Fig. 6 Internal Block Diagram for 스포츠 무료 분석L3526
The second feature is the ability of a single LED driver to support both constant current driving and constant voltage driving. By configuring the terminals, either constant current or constant voltage driving can be selected. The benefit of this feature is that it simplifies 스포츠 무료 분석ocurement and inventory management. There is no longer a need to 스포츠 무료 분석ocure two different types of drivers—one for constant current and one for constant voltage—allowing inventory management to be consolidated into one type.
The third feature is the enhanced electrostatic discharge (ESD) tolerance. This was achieved by optimizing the circuit design of the LED driver. Our internal testing confirmed that the device withstands 8 kV of ESD in the human body model (HBM). This surpasses many competitors' 스포츠 무료 분석oducts, which typically offer 2 kV.
The new 스포츠 무료 분석oduct is packaged in a 48-terminal QFN with a mounting area of 7 mm x 7 mm. The maximum drive current is 40 mA in constant current mode and 80 mA in constant voltage mode. The brightness adjustment supports up to 256 levels, and the supply voltage range is 4.5 V to 5.5 V.
With the launch of this new 스포츠 무료 분석oduct, our lineup of decorative LED drivers has been expanded. This allows manufacturers to select the most suitable LED driver according to the design philosophy of their amusement devices or arcade gaming machines.
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