Hi,
Using the Webench to do the following design using the TPS43601:
1. Vin = 6-9V
2. Vout = 12V
3. Output Current = 3A.
The design comes up with a 47A of MOSFETs and 13*10uF of output capacitors. Is that correct. from the data sheet the output caps are determined by the maximum transient response needed, how does the webench calculate the output caps? what transient response does he determine? Why such heavy current transistors are selected?
For another thing, there are 2 reference designs in the data sheet, if the current sense resistor in the input would of changed to a limit of 3.5A, could it be used as a reference design for a 3A load? I am asking this as the FETs in the 1st reference design is a NexFET capable of delivering 20A...of couse transients should be taken into considerations and BW, Loop response etc. but if the current limit would of change can this be optimized to a 3A design?
Both of the reference designs in the data sheet use a Pi-Filter to filter out unwanted noise on the current sense pins, but the webench doesn't support the Inductor feature, it recommends a resistor "star" formation, is it better to go with the data sheet on this case?
Thanks,
Ran