Problems with a source of 14V x 1.5A using TOP256EN
I mounted the power supply that was generated by PI 8.0. But it did not work correctly.
So managed to stabilize the voltage at 14V when I put a 470R 1W resistor in the output of the source. But I can not stream more than 1A. Even with a smaller current, the transformer gets very hot, reaching 70, 80 ° C.
In this project I am using a core EEL19. Simulates the source again with the same components and the program gave me different from the first data source, now with a transformer and EEL22 again be the TVS diode in the circuit Clamper.
Would like you to send me a bill actually a reliable source with the AC 85 to 265V 60Hz and output of 14V x 1.5A using TOP256EN.
Give preference to be used as TOP256EN buy many of these IC. I'm waiting for aid from you.
Comments
The resistor 470R I placed parallel to the capacitor C10, so only got the voltage of 14.3 volts. Without the resistor the voltage rises too. The circuit that hill, this is precisely what this note.
What steps should I check and procedures in relation to the operation?
In place of TOP253EN TOP256EN am using and also put a TVS diode in parallel aa 200V C3 and R1.
I should add something to the circuit or the design is correct.? If necessary, I can send the generated file to your e-mail, so that Mr can analyze.
We're from Brazil, here is a representative of you?
I've managed to source work. I changed the core of the transformer EEL19 to EEL22, and 14.2 V source provided at the outlet. I started doing the tests with a load of 15R at the exit and then moved on to 10R. With the ammeter measuring the output 1.42A. So that after a while both the IC (Top256EN), transformer T1 and the diode D7 (UF5401) overheats. The IC U1 had to put the sink. The T1 measure came to 60 ° C and the diode D7 (UF5401) reached about 80 ° C. Something must be revised or modified in this project? The calculation of the transformer is correct. The tests were made with the source at 90VAC input. And with both 220VAC 60HZ IC (TOP256EN) warmed a little less with the input voltage higher, but the transformer T1 and diode D7 kept very warm.
What ambient temperature are testing this under? If it is 40 or 50C your temperatures seem very reasonable.
What type of heatsink are you using on the device? We recommend a maximum IC temperature, measured at the source pin of around 100 to 110 C maximum.
Also an output diode temperature of 80 is acceptable depending upon your ambient temperature. Make sure to provide plenty of copper area to help in heatsinking the diode. The transformer is also an acceptable temperature.
If you look at RDR-242, which uses JX though, you can see the acceptable thermal performance on page 36 for reference. http://www.powerint.com/sites/default/files/PDFFiles/rdr242.pdf
I will have someone from our Sales team contact you. Thank you for your patience.
-Wesley
What was the problem when you first built the power supply? Did it not turn on? Not regulate? The designs created by PI Expert should work very well.
Could you please show me a schematic of the current power supply you are working on? I don't understand where you have put the 470 ohm resistor from what you have told me. Furthermore I can't troubleshoot the supply if I don't know the exact schematic used.
Could you provide drain current and waveform plots of the supply at a given input voltage and load? This will help me make sure the supply is operating as should be expected.
Lastly the transformer seems relatively hot assuming this was measured at room temperature (25 C). There may be something wrong here as well.