LM5163: Suitable for my requirement or not ?

Hi G Karthik,

The device should work fine until the peak inductor current is below the min OCP threshold of the device. You have to choose Inductor and switching frequency such that the peak inductor is always below the min.OCP threshold at max load current and max input.

You can use the excel tool LM5163-LM5164DESIGN-CALC Calculation tool | TI.com

Please fill the excel and get back to us.

Regards

Arpita

Hi ARPITA NATH, 

I have filled in the excel, I have attached the excel sheet with the values filled in. In case of LM5163 even having an output of 5V i am not bale to go higher than 0.5A, is that an excel restriction ?

Could you also explain about the input EMI filter, is it necessary or is it just for EMI related issues ? Is it given assuming that the input DC source is a SMPS ?

Because in my case the input DC source is a battery, would i still be needing the input emi filter ?

Thank you, LM5163_calculations.xlsm

G Karthik.

Hi G karthik,

Note that the device is rated for 0.5A output current only. This is not only a excel restriction, but also device rating.

For your switching frequency i.e. 300kHz and chosen inductor of 68uH, at I out=0.5A, I see the peak inductor current is below the min.OCP threshold. It should work fine.

For more understanding about EMI filter, please look into Simple Success with Conducted EMI and Radiated EMI for LMR160X0, 

AN-2162 Simple Success With Conducted EMI From DC-DC Converters (Rev. C)

Depending on the source impedance of the input supply bus, an electrolytic capacitor may be required at the input to ensure stability, particularly at low input voltage and high output current operating conditions. For more information follow datasheet section 7.3

Regards

Arpita

Hi ARPITA NATH, 

Thanks for the answer. Just wanted to clarify that the peak inductor current that you are talking about is the one in the buck inductor table Pk-to-Pk Ripple current that n this case refers to 171mApk-pk right ?

Thanks, 

G karthik.