What is isolated and non-isolated power supply?
Oct 25, 2021
When designing power circuits for embedded systems or selecting finished power supply modules, one of the important issues to consider is whether to use isolated or non-isolated power supply solutions. Before discussing, let’s first understand the concepts of isolation and non-isolation, and the main characteristics of the two.
1, The concept of isolation and non-isolation of power supply.
The isolation and non-isolation nature of power supply are mainly for switching power supplies. The common views in the industry are:
a) Isolated power supply: there is no direct electrical connection between the input circuit and the output circuit of the power supply, and the input and output are insulated high-impedance state, no current loop.
b) Non-isolated power supply: there is a direct current loop between the input and output, for example, the input and output share a common ground.
2, Advantages and disadvantages of isolated power supply and non-isolated power supply.
To select isolated or non-isolated power supplies, you need to understand what are the requirements for power supply of actual projects, but before that, you should understand the main differences between isolated and non-isolated power supplies:
a) Isolated module is with higher reliability, but the cost is relatively high and the efficiency is poor.
b) The non-isolated module has a simple structure, with low cost and high efficiency, but poor safety performance.
3, Isolated and non-isolated power supply application examples:
By understanding the advantages and disadvantages of isolated and non-isolated power supplies, we know that they have their own advantages. For some commonly used embedded power supply options, we can already make accurate judgments.
a) Where safety requirements are required, such as AC-DC from mains or medical power supply, to ensure personal safety, an isolated power supply must be used, and in some cases, a reinforced isolated power supply must be used.
b) In order to improve the anti-interference performance and ensure the reliability of the power supply of the front stage of the system, an isolated power supply is generally used
c) For external I/O ports, in order to ensure the reliable operation of the system, it is also recommended to isolate the I/O ports.
d) The IC or part of the circuit in the circuit board is powering, from the perspective of cost performance and volume, the non-isolated solution is preferred
e) For the power supply of long-distance industrial communication, in order to effectively reduce the influence of ground potential difference and wire coupling interference, an isolated power supply is generally used to power each communication node separately
f) For occasions that use battery power supply and have stringent endurance requirements, need to use non-isolated power supply.
For LIGHT VICTOR led lighting products, both isolated and non-isolated power supply solutions are available. For efficiency and cost reasons, most of lamps are with non-isolated power supply, but in terms of safety, the power supplies of high mast lighting are with isolated power supply. Please connect and let us know your needs, we can offer you the solution!
