Complex communication equipment and systems have put forward high requirements on the composition and performance of communication dedicated switching power supplies in many aspects.
1) DC power supply and (or) AC power supply
Modern communication equipment is generally electronic circuits and computer circuits, which require a variety of DC voltages for power supply. As a (communication) device, a conversion power supply (rectification, conversion, etc.) can also be provided inside, so the exterior of the (communication) device can be divided into DC power supply or AC power supply network. Usually, large-scale communication equipment and special equipment such as large-scale computers use DC power supply, considering the highest reliability; small general-purpose equipment uses AC power supply, whichever is more mobile.

2) Uninterrupted power supply
Uninterrupted power supply for communication equipment is extremely important. The reliability of the uninterrupted DC power supply system is directly guaranteed by the battery; the AC uninterrupted power supply system can also achieve uninterrupted power supply, but the reliability is lower than that of the DC uninterrupted power supply system.
3) The voltage is accurate and stable
For general digital circuits that are not demanding, it is 5V±0.25V. For 12-bit A/D converters (to ensure its resolution), the reference voltage must have an accuracy of 0.02%. For batteries that guarantee uninterrupted power supply The long-term float voltage should usually be (2.23V 0.02V)/only, otherwise the life of the expensive battery will be shortened.
4) Low noise voltage
The interference to communication is small, for example, the noise during voice communication is small, the fringe interference during image communication is small, and the bit error rate during effective word communication is low.
5) High efficiency
Energy saving, reduction of heat generation of power supply equipment, improvement of reliability, and reduction of equipment size and weight all require high efficiency. Many circuit technologies (soft switching, energy recovery, etc.) are developed for high efficiency.
6) Less pollution
It does not affect the quality of power supply of the power grid (greening), the input power factor is high, the input harmonic current is small, and the soft start is adopted to reduce the impact current.
7) Automatic protection
Once abnormal phenomena occur, such as excessive input and output voltage or current, excessive temperature rise, etc., protective measures such as cutting off the power supply should be taken immediately to avoid the expansion of the fault, and to ensure the normal power supply of the system.
8) Lightning protection and overvoltage protection
Lightning strikes and operating overvoltages of the power grid are environmental supply and distribution factors, but they are not uncommon, and are important factors that cause accidental damage to equipment.
9) Automatic monitoring and centralized control
Can save manpower and improve system reliability. The communication system has realized the centralized monitoring of some stations and districts of the Bureau of Communication and Evaluation, and is working towards centralized monitoring in cities, with the goal of centralized monitoring across the country.
10) Other
It can work normally within the specified environmental temperature and humidity range, with low failure rate and long life.