Other Parts Discussed in Thread: LM5165, LM5156
Hello,
- I am willing to design a buck converter based on LM5165 with the next specifications(the calculation file is attached):
- Based on LM5156 calculation file and datasheet I made the next implementation:
Form the datasheet and app notes (snvu474 ,snvu511) it seems that COT operation mode requires a minimum ESR, which in most of the cases is added externally (like in my schematic R2584, R2585) and based on this fact I have the next questions:
- The min ESR value shall be calculated at Input Voltage – Nom or Input Voltage – Min ?
- If an external capacitor with low ESR (by ex 100uF ESR<0.5ohm) Is connected to 13V5 output, will the converter work properly due to overall ESR reduction?
- What happens if the ESR condition is not met; the converter will not work properly?(poor stabilization, oscillation…)
- In order to reduce the output ripple and therefore external ESR a feedforward capacitor(mentioned on 2.5.2.1 datasheet) may be added in parallel with upper feedback resistor – C2586. Is there any relationship for dimensioning this capacitor?
Thank you!
