Hello...
I am designing a 450V power supply with 1mA max current. It needs to accept from 9V to 18V at the input.
I have design the circuit in the attached file and tested the prototype, however the current consumtion of the real circuit is double as the simulated. 50mA vs 10mA in stable state. It gives a very poor efficiency.
The TF used is a Coilcraft DA2032
Questions:
1. What could be causing this higher current consumption?
2. In the layout, I have the high voltage part in one side of the Tf and the rest in the other side. So For the feedback-resistive divider iks in the high voltage part and from there I have a looong track to the FBX pin. As it goes under the TF, the signal get really noisy. Any suggestion?
3. The transformer get a bit warm during operation. About 40C. Is it normal?
4. Any other topology you can recommend for this application?
Thanks in advance,
mfsd
I am designing a 450V power supply with 1mA max current. It needs to accept from 9V to 18V at the input.
I have design the circuit in the attached file and tested the prototype, however the current consumtion of the real circuit is double as the simulated. 50mA vs 10mA in stable state. It gives a very poor efficiency.
The TF used is a Coilcraft DA2032
Questions:
1. What could be causing this higher current consumption?
2. In the layout, I have the high voltage part in one side of the Tf and the rest in the other side. So For the feedback-resistive divider iks in the high voltage part and from there I have a looong track to the FBX pin. As it goes under the TF, the signal get really noisy. Any suggestion?
3. The transformer get a bit warm during operation. About 40C. Is it normal?
4. Any other topology you can recommend for this application?
Thanks in advance,
mfsd
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