Hello
I'm looking for information about VR5510 BUCK performances: I would like to use them in analog application where an LDO is the right choose: however VR5510 LDOs can be at limit current in some situation. I'm not able to find any information about voltage ripple specification of the BUCKs (referred to suggested output filter, I'm using). Is it possible to have? I found on this forum that other VRs have this kind of information but VR5510 doesn't.
I have an issue using VR5510 in companion with SJA1110. Short story long: if the SJA1110 is keep in HARD RESET and I power up the VR5510 from external source, the LDO2 connected to VDDIO 1.8V MII power supply rail startup in instability generating 2.2V instead of 1.8V (i think that voltage can rise up to Vin 3.3V if not limited by some SJA1110 internal clamp)
Attached the portion of the schematic from NXP SJA1110-EVM board that is exactly what I used on my custom board.
I'm monitoring the 1.8V voltage with VR5510 internal voltage monitors, in that case VR5510 PGOOD never change state because of OVERVOLTAGE detected.
Very strange thing is that if I disconnect PGOOD pin from SJA1110 HARD RESET pin, i have no issues and PMIC start successfully together with SJA1110.
Is there the possibility that LDO2 goes in instability due to high output load current and never recovers? OTP program is to autoretry every 4s but VR5510 never retry.
Thank you
enrov
