What SMPS bandwidth means ?

[Sahil_khan]

Dear guys

Can some body clarify/explain to me;

What does the bandwidth of SMPS means ? For example, if we look at the open loop bode plot of LC buck converter, we can see after the corner frequency there is a -40dB/decade slope which actually shows the attenuation of the signals after the corner frequency. Since we want for good filtering that all the signals should be attenuated and only DC component should be available at the output of a buck converter, in this scenario the bandwidth of a power supply should be as much smaller as possible in order to attenuate all the signals (but in practical high bandwidth power supplies are desired) WHY So ??

Thank you all.

Regards
Sahil

 

[sandipm14]

BUCK CONVERTER
FREQUENCY COMPENSATION
CIRCUIT
BUCK CONVERTER
FREQUENCY COMPENSATION
CIRCUIT







You can tell it's time to compensate a switch-mode power supply. Beads of sweat form on your brow. You reach for a handful of R and C components. You strain to remember some control theory you read long ago. I should know, it happens to me every time. But then you dive in, you struggle, and eventually - out of the ringing and oscillations - comes a response that begins to look normal. This topic pulls together a series of SMPS adventures - the Buck Converter - Voltage Control Mode, and the Buck Converter - AC Model - with frequency compensation as the final topic.




and more details please check below link.

http://www.ecircuitcenter.com/Circuits/smps_buck_comp/smps_buck_comp.htm

 

[FvM]

WHY So ??

Think about dynamic behaviour, e.g. response to load steps and suppression of input voltage variations.

 

[Sahil_khan]

@sandipm14; Sorry, I did not get the answer for my question.

- - - Updated - - -

Sorry I still do not understand can you explain please?