Renesas reveals 1 GHz GaN PA for CATV applications
The gallium nitride power amplifier grown on a silicon substrate offers approximately double the output performance of similar gallium arsenide based products.
Renesas Electronics has announced the development of the MC-7802, a GaN power amplifier module for 1GHz CATV (cable television) systems.
Designed for use as a power amplifier for applications such as trunk amplifiers for CATV systems, the MC-7802 achieves high output power and low distortion that are among the best in the industry today.
Renesas GaN Power Amplifier Module for CATV Applications Using the 1 GHz Band, the MC-7802
The MC-7802 module incorporates newly-developed GaN FETs that can be operated at higher frequencies and deliver higher output power than existing Renesas Electronics power amplifier module products based on GaAs. The MC-7802 provides approximately double the output performance while maintaining power consumption and distortion performance at the same levels as existing products.
This is achieved by optimising the matching circuits of the GaN FETs and other components for CATV applications. This enables manufacturers of CATV transmission equipment to roughly double output power without increasing energy consumption, so the coverage area of the CATV network overall can be expanded with no increase in power consumption.
The newly developed GaN FETs are fabricated on a silicon substrate instead of on a substrate made of SiC, the material typically used previously. The use of a silicon substrate rather than an expensive SiC substrate facilitates larger wafer sizes and will allow the MC-7802 to be more competitively priced.
Renesas Electronics regards the GaN FET as a key device and plans to expand its PA module product lineups for CATV to form a product family.
CATV power amplifier modules are mainly used in the trunk amplifiers of CATV systems, the optical node units of hybrid fibre coaxial (HFC) systems, and the final stages of booster power amplifiers for common receiver units installed in multiunit dwellings such as apartment buildings. These power amplifier modules are semiconductor devices that amplify multiple channel signals to make up for transmission loss over the network.
Since they amplify terrestrial digital TV, CATV, and Internet signals, their better linearity (distortion performance) secure more stable data transfer, and improved signal quality. The high output power provides greater flexibility in system design and makes it easier to keep costs down, allowing the network to be expanded by extending transmission distances and increasing the number of branches.
With increasing digitisation in recent years, CATV systems have gone beyond the simple distribution of video content and now also offer hybrid services including Internet access and Internet telephony (VoIP), and the number of channels handled has proliferated. As a result, the use of systems employing the 1 GHz band is expected to grow.
However, although systems employing the 1 GHz band can transmit more channels than existing systems (which use the 770 MHz or 870 MHz band, depending on the region), the higher number of channels brings issues such as increased output power and distortion. In addition, demand is rising for high-frequency semiconductor devices with high output power, low distortion, and energy efficiency for use in amplifiers that maximise the transmission distance and number of branches in order to reduce the transmission cost. The MC-7802 addresses this market demand by providing low power consumption together with improved output linearity and distortion characteristics.
Renesas regards the new MC-7802 device as a strategic product that will enable the company to enlarge its share of the market for CATV power amplifier devices, and aggressive sales promotion is planned in Japan, North America, Europe and China.
Renesas plans to follow up on the new MC-7802 device by developing and commercialising a family of similar products with a variety of gain performances. The company also has plans to continue development work on products incorporating GaN FETs for high-frequency applications and to steadily expand its line-up of such products.