Differences in the application range of synchronous rectification

So can synchronous rectification replace Schottky rectification?
Since synchronous rectification has such advantages over Schottky rectification, will there be a situation where synchronous rectification will unify the rivers and lakes on PC power supplies in the future? In fact, unless there is a strong enough force to promote this situation, everyone should not expect to see it for a long time in the future. Like the power supply topology, Schottky rectification and synchronous rectification are not technically distinguished. They are purely derived from different structures due to different needs, and they each have their own applicable fields. Although the current synchronous rectification is mature enough, in terms of the overall cost of the circuit, the Schottky diode still has an absolute advantage, after all, the latter does not require a special drive circuit.
Therefore, in some power products that are not sensitive to performance, but the overall cost is very tight, that is, what we often call "entry-level products" or "price-sensitive products", Schottky rectification still exists. value. However, it is also very difficult for Schottky rectifier to counterattack synchronous rectification. After all, the latter also has insurmountable advantages in electrical performance. Therefore, for mid-to-high-end products with "performance priority", synchronous rectification is basically It is already standard, and it is naturally the first choice for players who value power performance.

The loss of the switching power supply is mainly composed of three parts: the loss of the power switch tube, the loss of the high-frequency transformer, and the loss of the rectifier tube at the output end. In the case of low voltage and high current output, the conduction voltage drop of the rectifier diode is relatively high, and the loss of the rectifier tube at the output end is particularly prominent. Fast recovery diode (FRD) or ultrafast recovery diode (SRD) can reach 1.0~1.2V, even if a low-drop Schottky diode (SBD) is used, a voltage drop of about 0.6V will be generated, which leads to an increase in rectification loss. The synchronous rectification technology greatly reduces the rectification loss at the output end of the switching power supply, thereby improving the conversion efficiency and reducing the heating of the power supply itself.

5. The TB rectifier has lower loss and higher efficiency than the Schottky rectifier, but the Schottky rectifier has a simpler structure and simpler maintenance:
   TB rectifier is more efficient than Schottky rectifier power supply in low output voltage system due to voltage drop
   The TB rectifier is in the form of a chip package, while the Schottky rectifier is a modular package, and the installation of the TB rectifier is slightly more complicated
   Although the current capacity of TB rectifier tubes has increased in the past two years, the capacity is still smaller than that of Schottky tubes. Therefore, the number of TB rectifier tubes used in rectifier power supplies of the same current is at least twice as high as that of Schottky tubes.
6. What is the difference between high frequency switching power supply and thyristor rectifier? (Take 18V8000A as an example)
7. Efficiency:
   Thyristor rectifier: about 70%;
   High frequency switching power supply: 90%;
8. Transformer:
   Thyristor rectifier: composed of a power frequency transformer, very large in size and 200kg in weight;
   High frequency switching power supply: no power frequency transformer, high frequency transformer, weight 30kg;
9. Adjustment device:
   Thyristor rectifier: thyristor;
   High frequency switching power supply: IGBT;
10. Energy saving efficiency:
    Thyristor rectifier: bad;
    High frequency switching power supply: obvious power saving, compared with ordinary thyristor, it can save power by 15% to 30%;
11. Control circuit:
    Thyristor rectifier: complex, with synchronization requirements, not easy to integrate;
    High-frequency switching power supply: easy-to-use special printed circuit board, fully anti-corrosion treatment, completely sealed.