RADROCK Has Achieved a Breakthrough in Mass Production of Domestic High-Voltage Antenna Tuning Switches

Company news

2024.09.26

RADROCK Has Achieved a Breakthrough in Mass Production of Domestic High-Voltage Antenna Tuning Switches

1. Market value

With the vigorous construction and development of 5G at home and abroad, the current domestic 5G penetration rate has reached more than 85%, and the world average penetration rate has exceeded 50%, and the world average penetration rate will reach more than 80% in the next 3 to 5 years, and the share of 5G mobile phones has also been greatly improved.
For ordinary 4G mobile phones, due to the relatively simple structure and small number of antennas, there are generally 1 to 3 tuning switches; Due to the complex structure and function of 5G high-end mobile phones, the number of antennas has increased dramatically, and the antenna tuning switch can reach an astonishing 13 to 15.
According to the survey of professional institutions, antenna tuning products will increase at a compound growth rate of about 5% per year, reaching a total value of 1.9 billion US dollars in the next 3 to 5 years, and more than 10 billion market demand, but this market is still dominated by the United States, and domestic suppliers are still in the stage of vigorously catching up and breaking through.
With the continuous progress of domestic technology and the continuous growth of the supply chain, manufacturers attach importance to and vigorously invest in development to promote the continuous reduction of costs. Therefore, whether it is product performance or market share, domestic antenna tuning is accelerating to narrow the gap with international brands, gradually expand market share, and usher in vigorous development and transcendence.

(Figure-1 Source: Yole)

2.The background of the demand

With the continuous development of 5G and smartphones, mobile phones carry more and more applications and functions, and at the same time, they also bring great challenges to mobile phone antennas.
On the one hand, the emergence of new technologies and applications has prompted mobile phones to carry more antennas to meet the needs of numerous EN-DC combinations, carrier aggregation (CA), UL&DL MIMO, Wi-Fi MIMO, and satellite communications, while providing higher data rates. On the other hand, the addition of numerous 5G frequency bands and new application bands also requires mobile phone antennas to cover a wider frequency range, from the past Sub3GHz to Sub7GHz, as well as high-power design challenges such as GSM and 5G PC2 and high-orbit satellite communications.
To make matters more challenging, there is less and less space left for antenna design in mobile phones, resulting in less efficient antennas and a much more difficult design. Engineers must face significant design challenges in order to achieve higher overall performance, which has led to the use of high-performance antenna tuning products to aid in system design, enabling antennas to achieve efficient transceiver performance over a wider frequency range (from 600 MHz to 7 GHz) and in a more limited physical space, helping to increase battery life and support the slim design of mobile phones.

P=V²/R
(Assume P is constant, higher impedance causes higher voltage)
(Figure-2)

Antenna tuning is divided into impedance tuning (Fig.-3) and Aperture tuning (Fig.-4). Aperture tuning, on the other hand, can optimize antenna efficiency across multiple frequency bands by optimizing the length and resonance point of the antenna body, with a wide impedance range and low-voltage and high-voltage forms.
From the perspective of system design, high-voltage tuning can bring more performance improvement and benefits to the system, but the design of high-voltage antenna tuning switches is difficult, and the market is still dominated by products based on overseas processes. To sum up, the high-voltage antenna tuning switch not only plays an extremely important role in system design, but also represents the process and R&D design capabilities to a certain extent!

(Figure-3)

(Figure-2)

3. Design ability
Compared with the traditional switch design, the antenna tuning switch design is more focused on the ultimate performance improvement, Ruishi Chuangxin and the world's leading wafer partners jointly create a high-voltage process platform, the process itself Ron and Coff are deeply optimized, and the underlying layout is optimized to further improve the Ron and Coff of the antenna tuning switch.
In addition to the optimization of small signals, the core requirements of high-voltage antenna tuning switch are extremely high withstand voltage performance (defined as the harmonic nonlinear change point of the antenna tuning switch is Vpeak), usually the application scenario of RF devices will not exceed 40dBm RF power, while the definition of high-voltage antenna tuning switch for withstand voltage exceeds 48.1dBm power tolerance (converted to 80V RF voltage).
Traditional RF switch designs will meet the needs of higher withstand voltage through the stacking design of MOS tubes, but as the number of stacked MOS tubes increases, the problem of nonlinear growth of withstand power will occur, and it will also bring Ron degradation and area loss to the product. Ruishi Chuangxin optimizes the switch design through circuit design and layout layout, and improves the performance of the antenna tuning switch Vpeak without further loss of area and withstand voltage.
In addition to the optimization of the withstand voltage, the biggest difficulty of the high-voltage antenna tuning switch is that when the performance meets the requirements of Vpeak, it also needs to meet the harmonic requirements defined by 3GPP. Since 2020, Radrock has conquered the world's leading high-voltage harmonic cancellation technology and applied for a number of invention patents, which have been successfully applied in a variety of SRS switches and antenna tuning switch products. As shown in Figure 5, when the frequency is at 1880MHz, the 4*SPST antenna tuning switch still has enough margin for the 3rd harmonic in the worst All-Port test state, and the Vpeak can still meet the requirements of less than -40dBm at 85V.

(Figure-5)

4.Product capabilities
After various process exploration, product iteration and technical polishing, the first generation of high-voltage antenna tuning switch has been recognized by domestic well-known brand mobile phone customers. RR13124-11 is the most difficult high-voltage SP4T in a series of products, and has successfully achieved mass production and shipment, proving that Ruishi Chuangxin, as a young domestic RF supplier, has industry-leading product design and mass production capabilities.

(Figure-6)

MIPI SP4T RR13124-11
1.5mm*1.1mm
Vpeak 80V
1.6ohm Ron @DC
110fF Coff @900MHz
1.8V VIO
The SP4T has a built-in resonance stopper to suppress LC resonance

Compared with the international well-known brand competitors Vpeak and Harmonic, the test is as follows:

(Figure-7)

Radrock 1.5*1.1 size antenna tuning products are referred to as follows:

(Table-1)

Radrock's latest generation of small-profile antenna tuning switches are based on 12-inch wafers and advanced SOI processes, reducing the area by 25% compared to the previous generation, while enabling 1.2/1.8V low-voltage IO control, which is well adapted to a variety of new and existing platform interfaces.

(Figure-8)

MIPI SP4T RR13124-21
1.3mm*0.95mm
Vpeak 80V
1.8ohm Ron @DC
90fF Coff @900MHz
1.2V&1.8V VIO
The SP4T has a built-in resonance stopper to suppress LC resonance

Compared with the international well-known brand competitors Vpeak and Harmonic, the test is as follows:

(Figure-9)

锐石创芯 1.3*0.95尺寸天线调谐产品参考如下：

(Table-2)

5. Testing ability

Radrock has successfully built a number of test environments dedicated to high-voltage antenna tuning switches, covering comprehensive testing and verification performance from R&D to mass production, supporting customer individual evaluation and production assurance. In addition, Ruishi Chuangxin has independently developed a fully automatic test system, which supports important functions such as test plan editing and saving, dynamic curve display of test results, and test data comparison and playback, which realizes complete test automation and greatly improves test efficiency.

Radrock High Voltage Antenna Tuning Switch Automation Test Software
(Figure-10)

For 80V high-voltage RF testing, the system needs to provide 48dBm RF power, which is a great challenge for the test system, especially in the mass production test environment, to maintain such a high-power system, which is undoubtedly a very complex project. Radrock uses the method of matching an impedance tuner - Impedance tuner at the output end of the high-voltage antenna tuning switch to change the reflection coefficient (VSWR is usually 6:1) by adjusting the impedance to achieve the power superposition of the DUT side, and to measure the worst harmonic impedance point by changing the impedance phase, so as to realize the withstand voltage and harmonic measurement of the test specimen in one fell swoop.

6. Summary and outlook

Radrock has always attached great importance to the SOI product line, invested a lot of resources in both the R&D side and the market side, and continued to promote the in-depth process development with relevant Fab factories. After three years, it has not only achieved a large number of shipments in RF switches, but also has been highly recognized and praised by many domestic end customers. Today, it has achieved a major breakthrough in high-voltage antenna tuning products of domestic suppliers, which has greatly promoted the localization of high-voltage antenna tuning, so that end customers can have more differentiated choices in the supply chain, and escort the supply chain security of end customers in the changing geopolitical background.
Ruishi Chuangxin unswervingly moves forward on the road of localization, continuously cultivates and improves the performance of core products and focuses on reducing costs, vigorously strengthens the domestic supply chain, strategically plans the self-developed filter Fab and cooperates with the development of large modules such as L-PAMiD, L-DiFEM, DiFEM, etc., to continuously enhance market competitiveness, and also provide customers with full RF front-end solutions to make full preparations.
In the future, Radrock will continue to develop 120V high-voltage RF-MEMS products, tunable capacitors, and more than 100V RF-SOI products to meet diverse market needs.
More breakthroughs will be shown in subsequent articles, so stay tuned......

7. Company introduction

Radrock is a high-tech enterprise focusing on the R&D, manufacturing and sales of 4G and 5G RF front-end discrete devices and modules. The company has the design and modularization capabilities of a full range of chips required for RF front-end products, and strategically deploys filter wafer manufacturing. The company's products are widely used in smart phones, Internet of Things and smart wearable devices. Since its establishment, Radrock has adhered to the strategy of "science and technology innovation + domestic substitution", while actively exploring the localization of RF front-end core devices, through continuous technology research and development, it has formed strong core technical advantages in chip design, module integration scheme design, packaging and testing, etc., and has carried out a multi-faceted layout in filter design, manufacturing, packaging and testing, etc., accumulating sufficient potential energy for the company to continuously develop and iterate high-quality RF front-end products. The company has successively launched 4G Phase2, 5G Phase5N, Sub6G L-PAMiF, Sub3G L-PAMiD, WiFi FEM, filters, RF switches, antenna tuning switches, LNA Bank, diversity receiver module DiFEM, L-FEM and other RF front-end products to meet the huge demand for RF front-end products in domestic and foreign markets. As an excellent domestic RF supplier, Radrock takes PA as the core, continuously expands the product layout, from discrete to module product line comprehensive coverage, after 3 years of polishing, high-voltage antenna tuning products have achieved a breakthrough in mass production and shipment, and the new generation of products will soon be mass-produced, which has once again strengthened the layout of the entire RF front-end layout and strengthened its market position in the field of antenna tuning.