Current-Mode PWM chip

[joe_1]

Hi:

Anyone familiar with Current-Mode PWM chip?
Could you please explain to me how do they work in general?
Here is a link to one: https://www.electro-tech-online.com/custompdfs/2013/03/nte7096.pdf

Thanks.

 

[crutschow]

Basically it senses the triangular current waveform in the output inductor and uses that as part of the negative feedback to stabilize the voltage output control loop. It's somewhat simpler to stabilize than a straight voltage feedback control loop.

That particular device data sheet is unusual in that it doesn't show a typical application schematic, so it's not obvious how it's connected and what external components are needed. You might look at some other current-mode regulators from TI or Linear Technology which should have more complete data sheets to explain their operation.

Also here's a more detailed explanation if you are interested.

 

[ChrisP58]

The NTE7096 is a replacement for the Unitrode/TI UC3842.

https://www.ti.com/lit/gpn/uc3843

Also, read TI's ap notes slua101 and slua143.

https://www.ti.com/lit/an/slua101/slua101.pdf

https://www.ti.com/lit/an/slua143/slua143.pdf

 

[schmitt trigger]

If you can find Unitrode's app note U-100A, you'll have the most thorough explanation.

 

[schmitt trigger]

If you can find Unitrode's app note U-100A, you'll have the most thorough explanation.

Edit; The TI's notes on the post above include the old Unitrode app note.