A Brief Analysis of Innovative Energy Saving Solutions for LED Display Drivers Led by Chipone in the Low Carbon Era

Currently, in the context of state-of-the-art and carbon neutral policies, the entire industry is committed to actively achieving energy conservation and reduction in consumption of low-cost, high-efficiency products through the scientific and technological innovation. As the global industry leader in the field of LED display driver chip, Chipone’s R&D team has been deeply committed to various LED display low-power design innovations, in the goal of reducing the overall energy consumption of LED display from design source to energy-saving innovation to drive technology and lead the whole LED display industry to contribute to the ultimate achievement of global low-carbon sustainable development goals.

Talking about the importance of energy-saving innovation, Chipone LED Display Division Head said, as an innovation pioneer with over 50% global market share, one of the important research and development directions of Chipone LED division in the future. is definitely to realize the energy-saving innovation for the display driver. Because it is an essential social responsibility for any industry leader in the ESG field.

As LED screens get closer and closer, the challenges facing all display manufacturers are not only the higher demands on display performance, but also the difficulty of screen temperature. and energy consumption. The smooth implementation of “Baicheng Qianping” (a public LED screen upgrade program) has accelerated the implementation of outdoor LED advertising screens. In today’s low-carbon era, how to reduce the power consumption of displays has become an issue that needs to be addressed across the entire LED supply chain.

For the power composition of the large LED display, the main relevant elements include LED lamp bead, driver IC, controller, line loss, switching power conversion efficiency, most of the power composition is concentrated in the LED lamp bead and the power consumption of the IC driver in pixel pitch applications less than 1mm increases dramatically. According to the calculation formula P=V*I to reduce power consumption, design optimization and innovation can be made from the point of view of current and voltage. In this regard, Chipone can provide the following relevant technical solutions.

System voltage design optimization

1. Low-knee tension driver reduces power consumption by up to 20%

The low knee-voltage driver technology can ensure that under lower knee-voltage, the output current of the driver IC enters the constant current area and drives the LED lamp bead stably. Knee low voltage driver technology can reduce the power supply voltage of the whole system, thereby reducing the power consumption of the LED lamp bead and the driver IC. It can reduce power consumption by up to 20% compared to traditional driver scheme. Chipone’s driver ICs integrated with low elbow voltage driver technology include ICND2046, ICND2150S, ICND2159, ICND2069, etc.

Common solution

ICND2046

VR=5V

IR=20mA

VR=4V

IR=20mA

TB=5V

IG=15mA

TB=4V

IG=15mA

VB=5V

IB=8mA

VB=4V

IB=8mA

Power

27.5W

Power

22W

20% energy saving (only for the application conditions in the table above)
(27.5W—22W) ÷ 22W=20%

2. Common cathode driver reduces system power consumption by up to 30%

Since 2018, with the rapid development of Mini LED, common cathode driver has become a preferred driver solution. The traditional common anode driver solution adopts a unified power supply voltage, while the forward voltage of the red lamp is 1V lower than that of the green and blue lamps, so there is a loss caused by excessive voltage on the red light.

When the common cathode driver circuit is introduced, the additional power loss of the red lamp can be avoided by a separate power supply for the driver IC. The traditional RGB unified power supply mode can be changed to 2.8V and 3.8V power supply separately to reduce system power consumption by up to 30%. Chipone has developed and produced a number of common cathode driver ICs, including ICND2049, ICND2069, ICND2159, ICND2210, etc.

Figure : Product sample: ICND2159

Comparison of parameters of common cathode and common anode modules with the same specifications

Article

Common cathode (2069+2019)

common anode

Tension

R: 3V GB: 3.8V

5V

Running

6.4A

6.29A

Energy consumption

22.09W (30.7%↓)

31.45W

Initial lamp surface temperature

31°C

31°C

Lamp surface temperature after aging

43.5°C (12.4°C↓)

55.9°C

Red IC temperature

38.4°C (9.3°C↓)

47.7°C

Green IC temperature

43.4°C (6.4°C↓)

49.8°C

Blue IC temperature

41.3°C (5.9°C↓)

47.2°C

Circuit board temperature

40.8°C (7.4°C↓)

48.2°C

Optimization of the current system design

For LED lamp beads, under the condition of constant luminous efficiency, reducing the current of LED lamp beads will directly affect the brightness of the screen, while the use of bright LED lamp beads (efficiency high light) will significantly increase the cost. Therefore, the optimization of the current system design mainly focuses on the driver IC, and the design innovation can be achieved from the static power consumption reduction aspects of the driver IC, dynamic low power consumption and chip count reduction.

1. Low static power consumption design reduces power consumption by 20%-40%

In order to achieve stable and high precision current output and solve the problems such as low light quality coupling, 1st scan darkness and color deviation, the driver IC design contains the circuits complex digital and analog circuits such as current regulation module, precharge circuit, mbist circuit, detection module circuit, comparator and shift register. Although designing multiple circuit modules can improve display performance, it also requires greater power consumption, which poses great design challenges. From ICICN2053 (the first generation PWM driver) to ICND2153, Chipone has constantly made optimization and innovation in R&D and design, and reduced power consumption by 20%; in particular, the latest ICND2165 series products not only improve the image quality, but also reduce the power consumption by 40%, thus truly bringing an ideal innovation mode of “increasing performance and power consumption. declining energy.

2. Dynamic low-power design reduces screen power consumption by 5%-10% and standby power consumption by more than 50%

When a black screen occurs, the output channel of the traditional driver IC continues to be turned on, resulting in unnecessary current drain. Therefore, Chipone has specially developed the dynamic power-saving and black-screen power-saving technologies, which can be applied to close part of the channels or most of the circuit modules of the chip to achieve a Dynamic low power consumption based on different display images and detected data. by the control unit within a predetermined period of time. The power consumption for different display images can be reduced by 5%-10%, and the power consumption in standby mode can be reduced by more than 50%. Chipone’s driver ICs with dynamic low power function include ICND2055, ICND2069, etc.

3. Improved scanning design

In 2017, Chipone launched the first enhanced scan driver ICICND2065 supporting 1-64 scan lines, which led the industry to change from 32-line scan design to 64-line scan design. The improved scan design reduces the number of ICs by half, accompanied by lower power consumption and lower temperature, less PCB design difficulty and fewer PCB layers, higher efficiency connection, as well as a further reduction in the overall cost of the lamp board. Chipone has also successfully developed a 128-line scan driver, and it will further optimize and improve the driver architecture.

4. With highly integrated design, power consumption is only 20% of traditional 16-channel driver IC

To reduce the number of lamp board driver ICs, the number of scanning lines can be increased, or the degree of integration can be improved by increasing the number of driver IC channels, so as to reduce power consumption. driver IC energy. Chipone has successfully developed and produced a number of highly integrated driver ICs, including the traditional 16-channel driver IC, as well as 24-channel, 48-channel, 96-channel, 120-channel highly integrated driver ICs. channels and 360 channels with row and column in one. The super-integrated driver IC, with its static power consumption per pixel only 20% of that of the traditional 16-channel driver IC, is a preferred design solution and the driver IC especially in sub-0.9mm pixel pitch applications.

The advent of a low-carbon era has brought the key innovation area of ​​energy saving and consumption reduction for technical business innovation and growth. In the future, to achieve the sustainable and healthy development of the LED display industry, energy saving and consumption reduction innovation for the whole industrial chain will inevitably become a mandatory option. for each company. As the leader of LED display driver, Chipone will undoubtedly apply more advanced energy-saving and power-saving technologies to its own products in future R&D and design work, to promote the low-carbon upgrade of the entire industry.

Huang Wengang, Chipone Technology (Beijing) Co., Ltd.