What happens if the Input voltage and the output voltage are same in a boost converter?

[FreshmanNewbie]

I'd just like to know what would happen if the Input voltage and the output voltage are same in a boost converter. I have a feel that it might not work.

But would like to understand the effects that will happen on the inductor and the switching MOSFET.

This converter is an example.

 

[BradtheRad]

The boost converter adds supply voltage to whatever goes through the inductor. You can obtain supply voltage, unchanged, by turning off the switching device.

 

[KlausST]

Hi,

Your link does not work for me. Apparently you modified it manually. Usually you can´t get wrong and just press the LINK button ...

in more detail for decativated boost converters:

for usual boost converters (non sync) there is a voltage drop (according load current)
* in all wiring / traces
* evental series resistors / current measurement shunts
* the catch diode
where the catch diode will dominate, so expect 0.3V ... 1V of voltage drop.
An activated controller will compensate this drop.

for sync boost controllers, the diode may be overruled by the rectifier MOSFET, thus the expectable voltage drop may be way less than the usual voltage drop. It will depend on the IC whether the rectifier MOSFET will be activated or not.

Klaus

 

[FreshmanNewbie]

The boost converter adds supply voltage to whatever goes through the inductor. You can obtain supply voltage, unchanged, by turning off the switching device.

Thank you for the answer. So, in my above boost converter, since the MOSFET is internal, is there a option to turn the MOSFET OFF?

 

[crutschow]

in my above boost converter, since the MOSFET is internal, is there a option to turn the MOSFET OFF?

When all else fails, you might try looking at the data sheet (page 10).

 

[FreshmanNewbie]

When all else fails, you might try looking at the data sheet (page 10).

Which section on page 10? I did not get you.

 

[crutschow]

Which section on page 10? I did not get you.

 

[FreshmanNewbie]

W

View attachment 182011

Thank you. yes I did read this section. but what does it imply for my question?