RM8 multi output switching transformer for industrial SMPS
RM8
RM series switching transformer adopts RM type high-frequency low loss ferrite core and dedicated skeleton, specially designed for optimized design of small and medium power switching power supplies.
Download directory
Download directory
RM8 is a chamfered‑square RM core with a circular center post. It comes with two types of bobbins: DIP for through‑hole mounting and SMD for surface‑mount mounting. Its typical power ranges from 15‑60 W with an operating frequency of 20‑500 kHz. It is a counterpart to EE20 and is widely applied in flyback power supplies, isolated DC‑DC modules, industrial control systems, network communications, adapters, and small‑size LLC power supplies.
Product parameters
| Number of power supply phases | Multiphase | Frequency characteristic | High‑frequency |
| Brand | CXWON | Cooling form | Liquid/oil‑immersed |
| Cooling method | Oil‑immersed self‑cooled | Moisture‑proof methods | Potting‑type |
| Winding form | Autotransformer | Core shape | Type R |
| Appearance and Structure | Vertical type | Voltage ratio | 100 |
| Rated Power | 20 | Core form | Shell‑type |
Main transformer models：
Note:If you want to know more detailed information, simply click on"Contact Us"and we will answer all your questions one by one.
Core advantages of RM transformer
1.Round center‑pole design, easier winding, lower leakage inductance and better coupling performance.
2.Chamfered enclosed‑type core structure, minimal magnetic flux leakage, excellent EMI suppression, simplify EMC debugging.
3.Large effective core area Ae, high power density, compact footprint vs EE20.
4.Available in DIP through‑hole & SMD surface‑mount bobbins: 6+6 /7+7 /8+8 pins, support multi‑output windings.
5.Easy for safety isolation design, meets reinforced insulation, UL & CE safety requirements.
6.Compatible with PC40 / PC44 / PC95 ferrite material, low core loss, stable temperature‑rise performance.
7.Standard IEC core dimension, support both standard and custom winding solutions.
RM transformer real-shot details：
Typical application scenarios
Flowchart
Company Information:
FAQ
Q: What is the maximum leakage inductance of the RM8 transformer? What are the key factors affecting the leakage inductance?
A: The leakage inductance under the conventional process is controlled at 1.5% - 3% of the primary inductance; by using interleaved winding, Litz wire, and reasonable window allocation, it can be reduced to within 1%.
Key influencing factors: winding arrangement, insulation isolation thickness, number of turns, window utilization rate; the window space of RM8 is limited, and when pursuing extremely low leakage inductance, the winding scheme needs to be confirmed with the engineering.
A: The leakage inductance under the conventional process is controlled at 1.5% - 3% of the primary inductance; by using interleaved winding, Litz wire, and reasonable window allocation, it can be reduced to within 1%.
Key influencing factors: winding arrangement, insulation isolation thickness, number of turns, window utilization rate; the window space of RM8 is limited, and when pursuing extremely low leakage inductance, the winding scheme needs to be confirmed with the engineering.
Q: Can the RM magnetic core have air gaps? What topologies are suitable for it?
A: Air gaps can be opened. It is mainly used in flyback transformers to store excitation energy; the air gap can be a centralized air gap in the middle column or a distributed air gap at the interface. RM8 is mainly adapted to flyback topologies, but it can also be used in LLC and isolated DC-DC, and is not suitable for super-large power positive-boost topologies.
A: Air gaps can be opened. It is mainly used in flyback transformers to store excitation energy; the air gap can be a centralized air gap in the middle column or a distributed air gap at the interface. RM8 is mainly adapted to flyback topologies, but it can also be used in LLC and isolated DC-DC, and is not suitable for super-large power positive-boost topologies.
Q: What are the difficulties in the winding process of RM?
A: The window space of RM8 is compact. The circular middle column is suitable for fine wires and multi-strand twisted wires; the upper limit of window utilization rate is limited, and when the number of windings is too large, the winding difficulty increases; higher requirements are placed on winding alignment and insulation encapsulation processes, compared to the EE series, the factory process capability requirements are higher.
A: The window space of RM8 is compact. The circular middle column is suitable for fine wires and multi-strand twisted wires; the upper limit of window utilization rate is limited, and when the number of windings is too large, the winding difficulty increases; higher requirements are placed on winding alignment and insulation encapsulation processes, compared to the EE series, the factory process capability requirements are higher.
Q: What is the working temperature range of RM?
A: The magnetic core itself works at -40℃ to +125℃, and the upper limit of the final whole machine temperature is determined jointly by the insulation grade of the enameled wire and the material of the frame.
A: The magnetic core itself works at -40℃ to +125℃, and the upper limit of the final whole machine temperature is determined jointly by the insulation grade of the enameled wire and the material of the frame.
Q: Can RM8 be used as a shielded winding?
A: It supports adding copper foil shielding winding to further reduce EMI noise; however, it will occupy the window space, and window margin needs to be reserved during the design stage.
A: It supports adding copper foil shielding winding to further reduce EMI noise; however, it will occupy the window space, and window margin needs to be reserved during the design stage.
