search

sinara-hw / Urukul

4 channel 1GS/s DDS (AD9910 or AD9912 variant)
13 stars 7 forks source link

C155 #52

Closed hartytp closed 3 years ago

hartytp commented 4 years ago

@gkasprow given our experience with Fastino, do you think C155 (LT3045 output decoupling 22uF, X5R 16V, 0805) will be sufficient? That LDO needs 10uF min to ensure stability, so I wonder if this could be a bit marginal for the 7V output? My experience with other boards has been that when the capacitor is marginal some boards exhibit instability while others are fine, so it's best to err on the side of caution.

gkasprow commented 4 years ago

LEt's simply use higher capacitance

hartytp commented 4 years ago

Sounds good so long as we end up with >10uF after accounting for tolerance and bias.

As this is a bom change only and no new boards have been stuffed yet can we ask creotech and technoststem to make the change before shipping and also update the release?

gkasprow commented 4 years ago

we can change to 33uF without modifyig the PCB

dtcallcock commented 4 years ago

Can this be closed @gkasprow as it was changed in v1.5?

gkasprow commented 4 years ago

Yes, close it

gkasprow commented 4 years ago

In the new release, let's use 10+22uF or 33uF in bigger package. 33uF is difficult to obtain and increases the BOM count.

gkasprow commented 3 years ago

I added another 22uF capacitor