What is the typical usage of diodes in communication equipment?

1, Distribution of diode usage in communication equipment
The usage of diodes in communication equipment varies significantly due to device type, functional complexity, and technological generational differences. Taking a typical scenario as an example:
5G base station: A single macro base station requires approximately 2000-5000 diodes, covering RF front-end, power module, and signal processing unit. Among them, RF diodes (such as Schottky diodes and varactor diodes) account for over 40% and are used for frequency mixing, detection, and frequency synthesis; In the power module, there are approximately 1500 fast recovery diodes (FRDs) and silicon carbide (SiC) Schottky diodes, responsible for rectification and synchronous rectification to improve conversion efficiency; In addition, TVS diodes are used for port electrostatic protection, with a single base station demand of approximately 300 pieces.
Satellite communication equipment: A single low orbit satellite needs to carry about 100000 diodes, among which the varactor diode in the parametric amplifier is the core component. The usage of a single device exceeds 5000, and low-noise signal amplification is achieved through nonlinear reactance effect; Meanwhile, tunnel diode amplifiers are used for high-frequency signal processing, with a usage of approximately 2000 units per device.
Optical transmission module: In 400G/800G optical modules, photodiodes (such as PIN diodes and APD avalanche diodes) are the key to receiving and converting optical signals, with a single module usage of about 50-100 pieces; In addition, TVS diodes are used to protect high-speed signal lines, with a requirement of approximately 20 per module.
Consumer grade communication equipment: In smartphones, diodes are mainly used for RF front-end (such as switch diodes, detection diodes) and power management (such as synchronous rectification diodes), with a single device usage of about 500-800 pieces; In network devices such as routers, diodes are used for signal rectification and protection, with a usage of approximately 200-300 per device.
2, Core application scenarios of diodes in communication equipment
RF signal processing
RF diode is the "signal switch" of wireless communication systems, and its high-frequency characteristics (operating frequency covering MHz to GHz) and fast switching speed (nanosecond level) make it the core component of mixers, detectors, and frequency synthesizers. For example, in the Massive MIMO antenna of 5G base stations, Schottky diodes achieve ultrafast recovery (reverse recovery time<5ns) through metal semiconductor barriers, supporting signal synthesis of 64T64R large-scale antenna arrays; In satellite communication, varactor diodes adjust the capacitance value through bias voltage to achieve low-noise signal amplification of parametric amplifiers (noise temperature<0.02dB/K), meeting the high requirements for signal-to-noise ratio in deep space communication.
Power Management and Efficiency Optimization
The power module of communication equipment has strict requirements for the loss and thermal stability of diodes. Taking the 5G base station as an example, its 48V communication power supply adopts the collaborative design of GaN HEMT and SiC Schottky diode. The conduction voltage drop (Vf=0.3V) of SiC diode is reduced by 70% compared to traditional silicon-based devices, and the reverse recovery time (trr=10ns) is shortened by 80%, making the power conversion efficiency exceed 96%, and the annual power savings of a single base station exceed 100000 kWh. In the optical transmission module, synchronous rectification technology replaces traditional diodes with MOSFETs and combines low forward voltage drop (Vf=0.1V) Schottky diodes to increase the power efficiency of 400G optical modules from 85% to 94%, reducing the difficulty of thermal design.
Circuit protection and reliability enhancement
TVS diode is a "safety valve" for port protection in communication equipment. Its ultra fast response speed (<1ps) and high clamping accuracy (± 5%) can effectively suppress electrostatic discharge (ESD) and surge voltage. For example, in data center switches, Littelfuse unidirectional TVS diodes (such as SMAJ5.0A) optimize the PN junction structure to shorten the response time to 1ps, support 30kV air discharge protection for 10/1000Base-T Ethernet ports, and meet the IEC 61000-4-5 standard; In 5G small base stations, low parasitic capacitance TVS diodes (Cj=0.5pF) control signal attenuation below 0.1dB, supporting lossless transmission of PAM4 signals.
3, Technology Trends and Industry Prospects
Material innovation drives performance leap
The popularity of third-generation semiconductor materials (SiC, GaN) is reshaping the diode technology landscape. For example, GaN on Diamond substrate technology increases thermal conductivity to 1000W/(m · K), reduces diode junction temperature by 30 ℃, and prolongs device life; The integrated design of SiC MOSFET and diode enables the power density of 5G base station power modules to exceed 1kW/L, meeting the requirements of high-density deployment.
Intelligence and integration have become mainstream
In the future, diodes will develop towards the direction of "intelligent perception+self-regulation". For example, integrating temperature sensors, driving circuits, and protection functions on a single chip to achieve real-time monitoring and dynamic adjustment of diode junction temperature; In addition, the application of quantum tunneling effect, such as tunnel diodes, can enable switching actions to reach picosecond level, providing ultra-low loss solutions for 6G communication.
Localization substitution accelerates market restructuring
The size of China's TVS diode market will reach 12 billion yuan in 2023, a year-on-year increase of 15%, with the communication equipment sector accounting for 8.3%. Companies represented by Suzhou Gude have achieved a 70% reduction in reverse recovery time and an 80% reduction in conduction voltage drop through the research and development of SiC SBD diodes, breaking international monopolies; At the policy level, the national "TVS diode key technology research and development plan" has invested 5 billion yuan, focusing on supporting the research and development of high reliability and low-power technologies. It is expected that by 2025, China's TVS diode international market share will exceed 40%.