obiwan
New member
Hello friends.
I am new, and although I have experience in electronics, I am quite ignorant about SMPS and I am starting from scratch. So any wise suggestions are going to be very welcome.
I decided to start a project. I thought the simplest was using PI Expert software from Power Integrations to do what I really don't know which is calculating and building a SMPS transformer. The software gives almost every detail, from the schematic to the PCB when you select one of the PI chips. In my inexperience I thought that using this tool was good and that it should keep me into the boundaries of a more or less working approach.
I choose a 24 V @ 10 A rating for the output, and 175 to 265 VAC for mains because we have 220 VAC in my country. Trying to enter 85 VAC as lo value for mains was not accepted by the program, but I am happy with this range for a start. I obtained a complete schematic circuit and got all the components BOM from US distributors.
I am good drawing PCB's , so I ordered some boards following the manufacturer;s indications. I wil have the boards ready in a week or so.
In the meantime there is something that worries me, this is how to power up this SMPS considering some things such as the core gap. It is suggested but I know that I will have differences between the ideal design and mine. A friend build the transformer for me, he manufactures regular iron core transformers but he has no experience with ferrite. But he has the machines and we followed every single detail. The final product seems to be OK. We used EPCOS N87 material.
So, my question is: is there any more or less failsafe procedure to power-up this circuit ? What is the best thing to do ? Just turn it on and watch the smoke ? Ha ha ha !
Thank you in advance.
Obiwan
I am new, and although I have experience in electronics, I am quite ignorant about SMPS and I am starting from scratch. So any wise suggestions are going to be very welcome.
I decided to start a project. I thought the simplest was using PI Expert software from Power Integrations to do what I really don't know which is calculating and building a SMPS transformer. The software gives almost every detail, from the schematic to the PCB when you select one of the PI chips. In my inexperience I thought that using this tool was good and that it should keep me into the boundaries of a more or less working approach.
I choose a 24 V @ 10 A rating for the output, and 175 to 265 VAC for mains because we have 220 VAC in my country. Trying to enter 85 VAC as lo value for mains was not accepted by the program, but I am happy with this range for a start. I obtained a complete schematic circuit and got all the components BOM from US distributors.
I am good drawing PCB's , so I ordered some boards following the manufacturer;s indications. I wil have the boards ready in a week or so.
In the meantime there is something that worries me, this is how to power up this SMPS considering some things such as the core gap. It is suggested but I know that I will have differences between the ideal design and mine. A friend build the transformer for me, he manufactures regular iron core transformers but he has no experience with ferrite. But he has the machines and we followed every single detail. The final product seems to be OK. We used EPCOS N87 material.
So, my question is: is there any more or less failsafe procedure to power-up this circuit ? What is the best thing to do ? Just turn it on and watch the smoke ? Ha ha ha !
Thank you in advance.
Obiwan
