Modifying DI-124 for Lower Voltage Range

Hi Npatel,

Thank you for looking into our DI-124 as your base design. May I ask what is your preferred topology, output power and the PI part that you intend to use? With those information, you can use our online spreadsheet PIXls or PIExpert to provide you the closest schematic design.

Regards,

PI-Picard

Hello PI-Picard,

Any topology is fine as long as we can lower the cost. I think buck will be a cheaper option which does not use transformer. I used PIExpert with required parametres, but the lower voltage range is not available. Can you please suggest design using LNK304 or LNK305 using single phase input of 50 to 132 Vac, and 12V, 0.2A output, non-isolated is fine.

Thank you.

Hi Npatel,

If you will checked using the online PIXls it there will be errors if the minimum input voltage is 50Vac.

I will get back to you though on this.

Regards,
PI-Picard

Hi Npatel,

In our quick design checklist, we suggest ot use >70VDC at DC input voltage at maximum load condition and minimum input voltage to achieve the best performance of the power supply. However, the IC should still work if the DC bus voltage is higher than 50VDC at maximum load and minimum input voltage as the drain supply voltage is 50V. You should check if the all the performance is acceptable, like with low input voltage, the bus voltage ripple will be higher and output ripple will be worse. Same for efficiency,  thermal and EMI.

Regards,

PI-Picard

Thank you.

Can you please provide schematic for Buck converter using LNK305, 12v, 250mA output. 50-132Vacinput?

Hi Npatel,

You can use the sample circuits found in the DI-131 and from the datasheet. Refer to the attached spreadsheet for the input capacitor, inductor, freewheel diode and the feedback resistors.

Regards,

PI-Picard